import java.util.*;
import java.util.zip.*;
import java.util.List;
import java.util.regex.*;
import java.util.concurrent.*;
import java.util.concurrent.atomic.*;
import java.util.concurrent.locks.*;
import java.util.function.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
import javax.swing.table.*;
import java.io.*;
import java.net.*;
import java.lang.reflect.*;
import java.lang.ref.*;
import java.lang.management.*;
import java.security.*;
import java.security.spec.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.awt.geom.*;
import javax.imageio.*;
import java.math.*;
import java.text.NumberFormat;
import java.awt.geom.*;
import static x30_pkg.x30_util.DynamicObject;

class main {

static String str_px(int w, int h) {
  return n2(w) + "*" + n2(h) + "px";
}

static String str_px(WidthAndHeight image) {
  return image == null ? null : str_px(image.getWidth(), image.getHeight());
}
static String n2(long l) { return formatWithThousands(l); }
static String n2(AtomicLong l) { return n2(l.get()); }
static String n2(Collection l) { return n2(l(l)); }
static String n2(Map map) { return n2(l(map)); }

static String n2(double l, String singular) {
  return empty(singular) ? str(l) : n2(l, singular, singular + "s");
}

static String n2(double l, String singular, String plural) {
  if (fraction(l) == 0)
    return n2((long) l, singular, plural);
  else
    return l + " " + plural;
}

static String n2(long l, String singular, String plural) {
  return n_fancy2(l, singular, plural);
}

static String n2(long l, String singular) {
  return empty(singular) ? n2(l) : n_fancy2(l, singular, singular + "s");
}

static String n2(Collection l, String singular) {
  return n2(l(l), singular);
}

static String n2(Collection l, String singular, String plural) {
  return n_fancy2(l, singular, plural);
}

static String n2(Map m, String singular, String plural) {
  return n_fancy2(m, singular, plural);
}

static String n2(Map m, String singular) {
  return n2(l(m), singular);
}

static String n2(long[] a, String singular) { return n2(l(a), singular); }

static String n2(Object[] a, String singular) { return n2(l(a), singular); }
static String n2(Object[] a, String singular, String plural) { return n_fancy2(a, singular, plural); }




  static String n2(IMultiMap mm, String singular) { return n2(mm, singular, singular + "s"); }
static String n2(IMultiMap mm, String singular, String plural) {
    return n_fancy2(l(mm), singular, plural);
  }





static String formatWithThousands(long l) {
  return formatWithThousandsSeparator(l);
}


static int l(Object[] a) { return a == null ? 0 : a.length; }
static int l(boolean[] a) { return a == null ? 0 : a.length; }
static int l(byte[] a) { return a == null ? 0 : a.length; }
static int l(short[] a) { return a == null ? 0 : a.length; }
static int l(long[] a) { return a == null ? 0 : a.length; }
static int l(int[] a) { return a == null ? 0 : a.length; }
static int l(float[] a) { return a == null ? 0 : a.length; }
static int l(double[] a) { return a == null ? 0 : a.length; }
static int l(char[] a) { return a == null ? 0 : a.length; }
static int l(Collection c) { return c == null ? 0 : c.size(); }

static int l(Iterator i) { return iteratorCount_int_close(i); } // consumes the iterator && closes it if possible

static int l(Map m) { return m == null ? 0 : m.size(); }
static int l(CharSequence s) { return s == null ? 0 : s.length(); }
static long l(File f) { return f == null ? 0 : f.length(); }






  static int l(IMultiMap mm) { return mm == null ? 0 : mm.size(); }




















static boolean empty(Collection c) { return c == null || c.isEmpty(); }
static boolean empty(Iterable c) { return c == null || !c.iterator().hasNext(); }
static boolean empty(CharSequence s) { return s == null || s.length() == 0; }
static boolean empty(Map map) { return map == null || map.isEmpty(); }
static boolean empty(Object[] o) { return o == null || o.length == 0; }
static boolean empty(BitSet bs) { return bs == null || bs.isEmpty(); }


static boolean empty(Object o) {
  if (o instanceof Collection) return empty((Collection) o);
  if (o instanceof String) return empty((String) o);
  if (o instanceof Map) return empty((Map) o);
  if (o instanceof Object[]) return empty((Object[]) o);
  if (o instanceof byte[]) return empty((byte[]) o);
  if (o == null) return true;
  throw fail("unknown type for 'empty': " + getType(o));
}


static boolean empty(Iterator i) { return i == null || !i.hasNext(); }

static boolean empty(double[] a) { return a == null || a.length == 0; }
static boolean empty(float[] a) { return a == null || a.length == 0; }
static boolean empty(int[] a) { return a == null || a.length == 0; }
static boolean empty(long[] a) { return a == null || a.length == 0; }
static boolean empty(byte[] a) { return a == null || a.length == 0; }
static boolean empty(short[] a) { return a == null || a.length == 0; }




static boolean empty(IMultiMap mm) { return mm == null || mm.size() == 0; }


static boolean empty(File f) { return getFileSize(f) == 0; }










static boolean empty(Rect r) { return !(r != null && r.w != 0 && r.h != 0); }







static String str(Object o) {
  return o == null ? "null" : o.toString();
}

static String str(char[] c) {
  return new String(c);
}

static String str(char[] c, int offset, int count) {
  return new String(c, offset, count);
}


static double fraction(double d) {
  return d % 1;
}


static String n_fancy2(long l, String singular, String plural) {
  return formatWithThousandsSeparator(l) + " " + trim(l == 1 ? singular : plural);
}

static String n_fancy2(Collection l, String singular, String plural) {
  return n_fancy2(l(l), singular, plural);
}

static String n_fancy2(Map m, String singular, String plural) {
  return n_fancy2(l(m), singular, plural);
}

static String n_fancy2(Object[] a, String singular, String plural) {
  return n_fancy2(l(a), singular, plural);
}








static String formatWithThousandsSeparator(long l) {
  return NumberFormat.getInstance(new Locale("en_US")).format(l);
}


static <A> int iteratorCount_int_close(Iterator<A> i) { try {
  int n = 0;
  if (i != null) while (i.hasNext()) { i.next(); ++n; }
  if (i instanceof AutoCloseable) ((AutoCloseable) i).close();
  return n;
} catch (Exception __e) { throw rethrow(__e); } }


static RuntimeException fail() { throw new RuntimeException("fail"); }
static RuntimeException fail(Throwable e) { throw asRuntimeException(e); }
static RuntimeException fail(Object msg) { throw new RuntimeException(String.valueOf(msg)); }


static RuntimeException fail(Object... objects) { throw new Fail(objects); }


static RuntimeException fail(String msg) { throw new RuntimeException(msg == null ? "" : msg); }
static RuntimeException fail(String msg, Throwable innerException) { throw new RuntimeException(msg, innerException); }



static String getType(Object o) {
  return getClassName(o);
}


static long getFileSize(String path) {
  return path == null ? 0 : new File(path).length();
}

static long getFileSize(File f) {
  return f == null ? 0 : f.length();
}


static String trim(String s) { return s == null ? null : s.trim(); }
static String trim(StringBuilder buf) { return buf.toString().trim(); }
static String trim(StringBuffer buf) { return buf.toString().trim(); }




static RuntimeException rethrow(Throwable t) {
  
  if (t instanceof Error)
    _handleError((Error) t);
  
  throw t instanceof RuntimeException ? (RuntimeException) t : new RuntimeException(t);
}

static RuntimeException rethrow(String msg, Throwable t) {
  throw new RuntimeException(msg, t);
}


static RuntimeException asRuntimeException(Throwable t) {
  
  if (t instanceof Error)
    _handleError((Error) t);
  
  return t instanceof RuntimeException ? (RuntimeException) t : new RuntimeException(t);
}


static String getClassName(Object o) {
  return o == null ? "null" : o instanceof Class ? ((Class) o).getName() : o.getClass().getName();
}




static void _handleError(Error e) {
  //call(javax(), '_handleError, e);
}




static interface WidthAndHeight {
  default int w(){ return getWidth(); }
int getWidth();
  default int h(){ return getHeight(); }
int getHeight();
  
  public default Rect bounds() { return rect(0, 0, getWidth(), getHeight()); }
}
static class Fail extends RuntimeException implements IFieldsToList{
  Object[] objects;
  Fail() {}
  Fail(Object... objects) {
  this.objects = objects;}public Object[] _fieldsToList() { return new Object[] {objects}; }

  Fail(Throwable cause, Object... objects) {
    super(cause);
  this.objects = objects;
  }
  
  public String toString() { return joinNemptiesWithColon("Fail", commaCombine(getCause(), objects)); }
}


final static class Rect implements IFieldsToList{
  static final String _fieldOrder = "x y w h";
  int x;
  int y;
  int w;
  int h;
  Rect() {}
  Rect(int x, int y, int w, int h) {
  this.h = h;
  this.w = w;
  this.y = y;
  this.x = x;}

public boolean equals(Object o) {
if (!(o instanceof Rect)) return false;
    Rect __1 =  (Rect) o;
    return x == __1.x && y == __1.y && w == __1.w && h == __1.h;
}

  public int hashCode() {
    int h = 2543108;
    h = boostHashCombine(h, _hashCode(x));
    h = boostHashCombine(h, _hashCode(y));
    h = boostHashCombine(h, _hashCode(w));
    h = boostHashCombine(h, _hashCode(h));
    return h;
  }
  public Object[] _fieldsToList() { return new Object[] {x, y, w, h}; }

  Rect(Rectangle r) {
    x = r.x;
    y = r.y;
    w = r.width;
    h = r.height;
  }
  
  Rect(Pt p, int w, int h) {
  this.h = h;
  this.w = w; x = p.x; y = p.y; }
  Rect(Rect r) { x = r.x; y = r.y; w = r.w; h = r.h; }
  
  Rectangle getRectangle() {
    return new Rectangle(x, y, w, h);
  }
  
  public String toString() {
    return x + "," + y + " / " + w + "," + h;
  }
  
  int x1() { return x; }
  int y1() { return y; }
  int x2() { return x + w; }
  int y2() { return y + h; }
  
  boolean contains(Pt p) {
    return contains(p.x, p.y);
  }
  
  boolean contains(int _x, int _y) {
    return _x >= x && _y >= y && _x < x+w && _y < y+h;
  }
  
  boolean contains(Rectangle r) {
    return rectContains(this, r);
  }
  
  boolean empty() { return w <= 0 || h <= 0; }
  
  int getWidth() { return w; }
  int getHeight() { return h; }
}
static interface IFieldsToList {
  Object[] _fieldsToList();
}


static class Pt implements Comparable<Pt>, IDoublePt {
  int x, y;
  
  Pt() {}
  Pt(Point p) {
    x = p.x;
    y = p.y;
  }
  Pt(int x, int y) {
  this.y = y;
  this.x = x;}
  
  Point getPoint() {
    return new Point(x, y);
  }
  
  public boolean equals(Object o) {
    return o instanceof Pt && x == ((Pt) o).x && y == ((Pt) o).y;
  }
  
  public int hashCode() {
    return boostHashCombine(x, y);
  }
  
  // compare in scan order
  public int compareTo(Pt p) {
    if (y != p.y) return cmp(y, p.y);
    return cmp(x, p.x);
  }
  
  public String toString() {
    return x + ", " + y;
  }
  
  double length() { return sqrt(x*x+y*y); }
  
  public Pt minus(Pt p) { return ptMinus(this, p); }
  
  public double x_double() { return x; }
  public double y_double() { return y; }
}


interface IDoublePt {
  public double x_double();
  public double y_double();
}


static int getWidth(Component c) {
  return c == null ? 0 : (int) swingCall(c, "getWidth");
}


static int getHeight(Component c) {
  return c == null ? 0 : (int) swingCall(c, "getHeight");
}


static Rect rect(int x, int y, int w, int h) {
  return new Rect(x, y, w, h);
}

static Rect rect(Pt p, int w, int h) {
  return new Rect(p.x, p.y, w, h);
}

static Rect rect(int w, int h) {
  return new Rect(0, 0, w, h);
}




static String joinNemptiesWithColon(String... strings) {
  return joinNempties(": ", strings);
}

static String joinNemptiesWithColon(Collection<String> strings) {
  return joinNempties(": ", strings);
}


static String commaCombine(Object... l) {
  return joinNemptiesWithComma(flattenCollectionsAndArrays(ll(l)));
}


static int boostHashCombine(int a, int b) {
  return a ^ (b + 0x9e3779b9 + (a << 6) + (a >>> 2));
  
  // OLD (changed) 2022/3/10: ret a ^ (b + 0x9e3779b9 + (a << 6) + (a >> 2));
}


static int _hashCode(Object a) {
  return a == null ? 0 : a.hashCode();
}


static boolean contains(Collection c, Object o) {
  return c != null && c.contains(o);
}

static boolean contains(Iterable it, Object a) {
  if (it != null)
    for (Object o : it)
      if (eq(a, o))
        return true;
  return false;
}

static boolean contains(Object[] x, Object o) {
  if (x != null)
    for (Object a : x)
      if (eq(a, o))
        return true;
  return false;
}

static boolean contains(String s, char c) {
  return s != null && s.indexOf(c) >= 0;
}

static boolean contains(String s, String b) {
  return s != null && s.indexOf(b) >= 0;
}

static boolean contains(BitSet bs, int i) {
  return bs != null && bs.get(i);
}




static boolean contains(Rect r, Pt p) { return rectContains(r, p); }



static boolean rectContains(int x1, int y1, int w, int h, Pt p) {
  return p.x >= x1 && p.y >= y1 && p.x < x1+w && p.y < y1+h;
}

static boolean rectContains(Rect a, Rect b) {
  return b.x >= a.x && b.y >= a.y && b.x2() <= a.x2() && b.y2() <= a.y2();
}

static boolean rectContains(Rect a, Rectangle b) {
  return rectContains(a, toRect(b));
}

static boolean rectContains(Rect a, int x, int y) {
  return a != null && a.contains(x, y);
}

static boolean rectContains(Rect a, Pt p) {
  return a != null && p != null && a.contains(p);
}


static int cmp(Number a, Number b) {
  return a == null ? b == null ? 0 : -1 : cmp(a.doubleValue(), b.doubleValue());
}

static int cmp(double a, double b) {
  return a < b ? -1 : a == b ? 0 : 1;
}

static int cmp(int a, int b) {
  return a < b ? -1 : a == b ? 0 : 1;
}

static int cmp(long a, long b) {
  return a < b ? -1 : a == b ? 0 : 1;
}

static int cmp(Object a, Object b) {
  if (a == null) return b == null ? 0 : -1;
  if (b == null) return 1;
  return ((Comparable) a).compareTo(b);
}


static double sqrt(double x) {
  return Math.sqrt(x);
}


static Pt ptMinus(Pt a, Pt b) {
  if (b == null) return a;
  return new Pt(a.x-b.x, a.y-b.y);
}




static Object swingCall(final Object o, final String method, final Object... args) {
  return swing(new F0<Object>() { public Object get() { try {  return call(o, method, args);  } catch (Exception __e) { throw rethrow(__e); } }
  public String toString() { return "return call(o, method, args);"; }});
}


static String joinNempties(String sep, Object... strings) {
  return joinStrings(sep, strings);
}

static String joinNempties(String sep, Iterable strings) {
  return joinStrings(sep, strings);
}


static String joinNemptiesWithComma(Object... strings) {
  return joinNempties(", ", strings);
}

static String joinNemptiesWithComma(Iterable strings) {
  return joinNempties(", ", strings);
}


static List flattenCollectionsAndArrays(Iterable a) {
  List l = new ArrayList();
  for (Object x : a)
    if (x instanceof Collection)
      l.addAll(flattenCollectionsAndArrays((Collection) x));
    else if (x instanceof Object[])
      l.addAll(flattenCollectionsAndArrays(asList((Object[]) x)));
    else
      l.add(x);
  return l;
}


static <A> List<A> ll(A... a) {
  ArrayList l = new ArrayList(a.length);
  if (a != null) for (A x : a) l.add(x);
  return l;
}


static boolean eq(Object a, Object b) {
  return a == b || a != null && b != null && a.equals(b);
}


// a little kludge for stuff like eq(symbol, "$X")
static boolean eq(Symbol a, String b) {
  return eq(str(a), b);
}





static Rect toRect(Rectangle r) {
  return r == null ? null : new Rect(r);
}

static Rect toRect(RectangularShape r) {
  return r == null ? null : toRect(r.getBounds());
}



static Rect toRect(Rect r) { return r; }




static Object swing(Object f) {
  return swingAndWait(f);
}

static void swing(Runnable f) {
  swingAndWait(f);
}

static <A> A swing(F0<A> f) {
  return (A) swingAndWait(f);
}

static <A> A swing(IF0<A> f) {
  return (A) swingAndWait(f);
}


static Object call(Object o) {
  return callF(o);
}

// varargs assignment fixer for a single string array argument
static Object call(Object o, String method, String[] arg) {
  return call(o, method, new Object[] {arg});
}

static Object call(Object o, String method, Object... args) {
  //ret call_cached(o, method, args);
  return call_withVarargs(o, method, args);
}


static String joinStrings(String sep, Object... strings) {
  return joinStrings(sep, Arrays.asList(strings));
}

static String joinStrings(String sep, Iterable strings) {
  StringBuilder buf = new StringBuilder();
  for (Object o : unnull(strings)) { 
    String s = strOrNull(o);
    if (nempty(s)) {
      if (nempty(buf)) buf.append(sep);
      buf.append(s);
    }
  }
  return str(buf);
}


// unclear semantics as to whether return null on null

static <A> ArrayList<A> asList(A[] a) {
  return a == null ? new ArrayList<A>() : new ArrayList<A>(Arrays.asList(a));
}

static ArrayList<Integer> asList(int[] a) {
  if (a == null) return null;
  ArrayList<Integer> l = emptyList(a.length);
  for (int i : a) l.add(i);
  return l;
}

static ArrayList<Long> asList(long[] a) {
  if (a == null) return null;
  ArrayList<Long> l = emptyList(a.length);
  for (long i : a) l.add(i);
  return l;
}

static ArrayList<Float> asList(float[] a) {
  if (a == null) return null;
  ArrayList<Float> l = emptyList(a.length);
  for (float i : a) l.add(i);
  return l;
}

static ArrayList<Double> asList(double[] a) {
  if (a == null) return null;
  ArrayList<Double> l = emptyList(a.length);
  for (double i : a) l.add(i);
  return l;
}

static ArrayList<Short> asList(short[] a) {
  if (a == null) return null;
  ArrayList<Short> l = emptyList(a.length);
  for (short i : a) l.add(i);
  return l;
}

static <A> ArrayList<A> asList(Iterator<A> it) {
  ArrayList l = new ArrayList();
  if (it != null)
    while (it.hasNext())
      l.add(it.next());
  return l;  
}

// disambiguation
static <A> ArrayList<A> asList(IterableIterator<A> s) {
  return asList((Iterator) s);
}

static <A> ArrayList<A> asList(Iterable<A> s) {
  if (s instanceof ArrayList) return (ArrayList) s;
  ArrayList l = new ArrayList();
  if (s != null)
    for (A a : s)
      l.add(a);
  return l;
}



static <A> ArrayList<A> asList(Enumeration<A> e) {
  ArrayList l = new ArrayList();
  if (e != null)
    while (e.hasMoreElements())
      l.add(e.nextElement());
  return l;
}




static <A> List<A> asList(Pair<A, A> p) {
  return p == null ? null : ll(p.a, p.b);
}



static int iround(double d) {
  return (int) Math.round(d);
}


static int iround(Number n) {
  return iround(toDouble(n));
}





static void swingAndWait(Runnable r) { try {
  if (isAWTThread())
    r.run();
  else
    EventQueue.invokeAndWait(addThreadInfoToRunnable(r));
} catch (Exception __e) { throw rethrow(__e); } }

static Object swingAndWait(final Object f) {
  if (isAWTThread())
    return callF(f);
  else {
    final Var result = new Var();
    swingAndWait(new Runnable() {  public void run() { try { 
      result.set(callF(f));
    
} catch (Exception __e) { throw rethrow(__e); } }  public String toString() { return "result.set(callF(f));"; }});
    return result.get();
  }
}



static Map<Class, ArrayList<Method>> callF_cache = newDangerousWeakHashMap();



  static <A> A callF(F0<A> f) {
    return f == null ? null : f.get();
  }



  static <A, B> B callF(F1<A, B> f, A a) {
    return f == null ? null : f.get(a);
  }



  static <A> A callF(IF0<A> f) {
    return f == null ? null : f.get();
  }



  static <A, B> B callF(IF1<A, B> f, A a) {
    return f == null ? null : f.get(a);
  }


static <A, B> B callF(A a, IF1<A, B> f) {
  return f == null ? null : f.get(a);
}






  static <A> void callF(VF1<A> f, A a) {
    if (f != null) f.get(a);
  }


static <A> void callF(A a, IVF1<A> f) {
  if (f != null) f.get(a);
}

static <A> void callF(IVF1<A> f, A a) {
  if (f != null) f.get(a);
}


static Object callF(Runnable r) { { if (r != null) r.run(); } return null; }


static Object callF(Object f, Object... args) {
  
    
  return safeCallF(f, args);
}

static Object safeCallF(Object f, Object... args) {
  if (f instanceof Runnable) {
    ((Runnable) f).run();
    return null;
  }
  if (f == null) return null;
  
  Class c = f.getClass();
  ArrayList<Method> methods;
  synchronized(callF_cache) {
    methods = callF_cache.get(c);
    if (methods == null)
      methods = callF_makeCache(c);
  }
  
  int n = l(methods);
  if (n == 0) {
    
    
    if (f instanceof String)
      throw fail("Legacy call: " + f);
    
    throw fail("No get method in " + getClassName(c));
  }
  if (n == 1) return invokeMethod(methods.get(0), f, args);
  for (int i = 0; i < n; i++) {
    Method m = methods.get(i);
    if (call_checkArgs(m, args, false))
      return invokeMethod(m, f, args);
  }
  throw fail("No matching get method in " + getClassName(c));
}

// used internally
static ArrayList<Method> callF_makeCache(Class c) {
  ArrayList<Method> l = new ArrayList();
  Class _c = c;
  do {
    for (Method m : _c.getDeclaredMethods())
      if (m.getName().equals("get")) {
        makeAccessible(m);
        l.add(m);
      }
    if (!l.isEmpty()) break;
    _c = _c.getSuperclass();
  } while (_c != null);
  callF_cache.put(c, l);
  return l;
}





static Object call_withVarargs(Object o, String methodName, Object... args) { try {
  if (o == null) return null;
  
  if (o instanceof Class) {
    Class c = (Class) o;
    _MethodCache cache = callOpt_getCache(c);
    
    Method me = cache.findStaticMethod(methodName, args);
    if (me != null)
      return invokeMethod(me, null, args);
      
    // try varargs
    List<Method> methods = cache.cache.get(methodName);
    if (methods != null) methodSearch: for (Method m : methods) {
      { if (!(m.isVarArgs())) continue; }
      { if (!(isStaticMethod(m))) continue; }
      Object[] newArgs = massageArgsForVarArgsCall(m, args);
      if (newArgs != null)
        return invokeMethod(m, null, newArgs);
    }
    
    throw fail("Method " + c.getName() + "." + methodName + "(" + joinWithComma(classNames(args)) + ") not found");
  } else {
    Class c = o.getClass();
    _MethodCache cache = callOpt_getCache(c);

    Method me = cache.findMethod(methodName, args);
    if (me != null)
      return invokeMethod(me, o, args);
      
    // try varargs
    List<Method> methods = cache.cache.get(methodName);
    if (methods != null) methodSearch: for (Method m : methods) {
      { if (!(m.isVarArgs())) continue; }
      Object[] newArgs = massageArgsForVarArgsCall(m, args);
      if (newArgs != null)
        return invokeMethod(m, o, newArgs);
    }
    
    throw fail("Method " + c.getName() + "." + methodName + "(" + joinWithComma(classNames(args)) + ") not found");
  }
} catch (Exception __e) { throw rethrow(__e); } }


static String unnull(String s) {
  return s == null ? "" : s;
}

static <A> Collection<A> unnull(Collection<A> l) {
  return l == null ? emptyList() : l;
}

static <A> List<A> unnull(List<A> l) { return l == null ? emptyList() : l; }
static int[] unnull(int[] l) { return l == null ? emptyIntArray() : l; }
static char[] unnull(char[] l) { return l == null ? emptyCharArray() : l; }
static double[] unnull(double[] l) { return l == null ? emptyDoubleArray() : l; }

static <A, B> Map<A, B> unnull(Map<A, B> l) {
  return l == null ? emptyMap() : l;
}

static <A> Iterable<A> unnull(Iterable<A> i) {
  return i == null ? emptyList() : i;
}

static <A> A[] unnull(A[] a) {
  return a == null ? (A[]) emptyObjectArray() : a;
}

static BitSet unnull(BitSet b) {
  return b == null ? new BitSet() : b;
}


static Pt unnull(Pt p) {
  return p == null ? new Pt() : p;
}


//ifclass Symbol

static Symbol unnull(Symbol s) {
  return s == null ? emptySymbol() : s;
}
//endif



static <A, B> Pair<A, B> unnull(Pair<A, B> p) {
  return p != null ? p : new Pair(null, null);
}


static int unnull(Integer i) { return i == null ? 0 : i; }
static long unnull(Long l) { return l == null ? 0L : l; }
static double unnull(Double l) { return l == null ? 0.0 : l; }


static String strOrNull(Object o) {
  return o == null ? null : str(o);
}


static boolean nempty(Collection c) {
  return !empty(c);
}

static boolean nempty(CharSequence s) {
  return !empty(s);
}

static boolean nempty(Object[] o) { return !empty(o); }
static boolean nempty(byte[] o) { return !empty(o); }
static boolean nempty(int[] o) { return !empty(o); }

static boolean nempty(BitSet bs) { return !empty(bs); }

static boolean nempty(Map m) {
  return !empty(m);
}

static boolean nempty(Iterator i) {
  return i != null && i.hasNext();
}


static boolean nempty(IMultiMap mm) { return mm != null && mm.size() != 0; }



static boolean nempty(Object o) { return !empty(o); }









static boolean nempty(Rect r) { return r != null && r.w != 0 && r.h != 0; }







static ArrayList emptyList() {
  return new ArrayList();
  //ret Collections.emptyList();
}

static ArrayList emptyList(int capacity) {
  return new ArrayList(max(0, capacity));
}

// Try to match capacity
static ArrayList emptyList(Iterable l) {
  return l instanceof Collection ? emptyList(((Collection) l).size()) : emptyList();
}

static ArrayList emptyList(Object[] l) {
  return emptyList(l(l));
}

// get correct type at once
static <A> ArrayList<A> emptyList(Class<A> c) {
  return new ArrayList();
}


static double toDouble(Object o) {
  if (o instanceof Number)
    return ((Number) o).doubleValue();
  if (o instanceof BigInteger)
    return ((BigInteger) o).doubleValue();
  if (o instanceof String)
    return parseDouble((String) o);
  if (o == null) return 0.0;
  throw fail(o);
}




// TODO: test if android complains about this
static boolean isAWTThread() {
  if (isAndroid()) return false;
  if (isHeadless()) return false;
  return isAWTThread_awt();
}

static boolean isAWTThread_awt() {
  return SwingUtilities.isEventDispatchThread();
}


static Runnable addThreadInfoToRunnable(final Object r) {
  final Object info = _threadInfo();
  return info == null ? asRunnable(r) : new Runnable() {  public void run() { try {  _inheritThreadInfo(info); callF(r); 
} catch (Exception __e) { throw rethrow(__e); } }  public String toString() { return "_inheritThreadInfo(info); callF(r);"; }};
}


static <A, B> Map<A, B> newDangerousWeakHashMap() {
  return _registerDangerousWeakMap(synchroMap(new WeakHashMap()));
}

// initFunction: voidfunc(Map) - is called initially, and after clearing the map
static <A, B> Map<A, B> newDangerousWeakHashMap(Object initFunction) {
  return _registerDangerousWeakMap(synchroMap(new WeakHashMap()), initFunction);
}


static Object invokeMethod(Method m, Object o, Object... args) { try {
  try {
    return m.invoke(o, args);
  } catch (InvocationTargetException e) {
    throw rethrow(getExceptionCause(e));
  } catch (IllegalArgumentException e) {
    throw new IllegalArgumentException(e.getMessage() + " - was calling: " + m + ", args: " + joinWithSpace(classNames(args)));
  }
} catch (Exception __e) { throw rethrow(__e); } }


static boolean call_checkArgs(Method m, Object[] args, boolean debug) {
  Class<?>[] types = m.getParameterTypes();
  if (types.length != l(args)) {
    if (debug)
      print("Bad parameter length: " + args.length + " vs " + types.length);
    return false;
  }
  for (int i = 0; i < types.length; i++) {
    Object arg = args[i];
    if (!(arg == null ? !types[i].isPrimitive()
      : isInstanceX(types[i], arg))) {
      if (debug)
        print("Bad parameter " + i + ": " + arg + " vs " + types[i]);
      return false;
    }
  }
  return true;
}


static Field makeAccessible(Field f) {
  try {
    f.setAccessible(true);
  } catch (Throwable e) {
    // Note: The error reporting only works with Java VM option --illegal-access=deny
    
    vmBus_send("makeAccessible_error", e, f);
    
  }
  return f;
}

static Method makeAccessible(Method m) {
  try {
    m.setAccessible(true);
  } catch (Throwable e) {
    
    vmBus_send("makeAccessible_error", e, m);
    
  }
  return m;
}

static Constructor makeAccessible(Constructor c) {
  try {
    c.setAccessible(true);
  } catch (Throwable e) {
    
    vmBus_send("makeAccessible_error", e, c);
    
  }
  return c;
}


static final Map<Class, _MethodCache> callOpt_cache = newDangerousWeakHashMap();

static Object callOpt_cached(Object o, String methodName, Object... args) { try {
  if (o == null) return null;
  
  if (o instanceof Class) {
    Class c = (Class) o;
    _MethodCache cache = callOpt_getCache(c);
    
    // TODO: (super-rare) case where method exists static and non-static
    // with different args
    
    Method me = cache.findMethod(methodName, args);
    if (me == null || (me.getModifiers() & Modifier.STATIC) == 0) return null;
    return invokeMethod(me, null, args);
  } else {
    Class c = o.getClass();
    _MethodCache cache = callOpt_getCache(c);

    Method me = cache.findMethod(methodName, args);
    if (me == null) return null;
    return invokeMethod(me, o, args);
  }
} catch (Exception __e) { throw rethrow(__e); } }

// no longer synchronizes! (see #1102990)
static _MethodCache callOpt_getCache(Class c) {
  _MethodCache cache = callOpt_cache.get(c);
  if (cache == null)
    callOpt_cache.put(c, cache = new _MethodCache(c));
  return cache;
}


static boolean isStaticMethod(Method m) {
  return methodIsStatic(m);
}


static Object[] massageArgsForVarArgsCall(Executable m, Object[] args) {
  Class<?>[] types = m.getParameterTypes();
  int n = types.length-1, nArgs = l(args);
  if (nArgs < n) return null;
  for (int i = 0; i < n; i++)
    if (!argumentCompatibleWithType(args[i], types[i]))
      return null;
  Class varArgType = types[n].getComponentType();
  for (int i = n; i < nArgs; i++)
    if (!argumentCompatibleWithType(args[i], varArgType))
      return null;
  Object[] newArgs = new Object[n+1];
  arraycopy(args, 0, newArgs, 0, n);
  
  // TODO: optimize
  
  int nVarArgs = nArgs-n;
  Object varArgs = Array.newInstance(varArgType, nVarArgs);
  for (int i = 0; i < nVarArgs; i++)
    Array.set(varArgs, i, args[n+i]);
    
  newArgs[n] = varArgs;
  return newArgs;
}


static <A> String joinWithComma(Collection<A> c) {
  return join(", ", c);
}

static String joinWithComma(Object... c) {
  return join(", ", c);
}

static String joinWithComma(String... c) {
  return join(", ", c);
}


static String joinWithComma(Pair p) {
  return p == null ? "" : joinWithComma(str(p.a), str(p.b));
}



static List<String> classNames(Collection l) {
  return getClassNames(l);
}

static List<String> classNames(Object[] l) {
  return getClassNames(asList(l));
}


static int[] emptyIntArray_a = new int[0];
static int[] emptyIntArray() { return emptyIntArray_a; }


static char[] emptyCharArray = new char[0];
static char[] emptyCharArray() { return emptyCharArray; }


static double[] emptyDoubleArray = new double[0];
static double[] emptyDoubleArray() { return emptyDoubleArray; }


static Map emptyMap() {
  return new HashMap();
}


static Object[] emptyObjectArray_a = new Object[0];
static Object[] emptyObjectArray() { return emptyObjectArray_a; }


static Symbol emptySymbol_value;

static Symbol emptySymbol() {
  if (emptySymbol_value == null) emptySymbol_value = symbol("");
  return emptySymbol_value;
}


static int max(int a, int b) { return Math.max(a, b); }
static int max(int a, int b, int c) { return max(max(a, b), c); }
static long max(int a, long b) { return Math.max((long) a, b); }
static long max(long a, long b) { return Math.max(a, b); }
static double max(int a, double b) { return Math.max((double) a, b); }
static float max(float a, float b) { return Math.max(a, b); }
static double max(double a, double b) { return Math.max(a, b); }

static int max(Collection<Integer> c) {
  int x = Integer.MIN_VALUE;
  for (int i : c) x = max(x, i);
  return x;
}

static double max(double[] c) {
  if (c.length == 0) return Double.MIN_VALUE;
  double x = c[0];
  for (int i = 1; i < c.length; i++) x = Math.max(x, c[i]);
  return x;
}

static float max(float[] c) {
  if (c.length == 0) return Float.MAX_VALUE;
  float x = c[0];
  for (int i = 1; i < c.length; i++) x = Math.max(x, c[i]);
  return x;
}

static byte max(byte[] c) {
  byte x = -128;
  for (byte d : c) if (d > x) x = d;
  return x;
}

static short max(short[] c) {
  short x = -0x8000;
  for (short d : c) if (d > x) x = d;
  return x;
}

static int max(int[] c) {
  int x = Integer.MIN_VALUE;
  for (int d : c) if (d > x) x = d;
  return x;
}

static <A extends Comparable<A>> A max(A a, A b) {
  return cmp(a, b) >= 0 ? a : b;
}


static double parseDouble(String s) {
  return empty(s) ? 0.0 : Double.parseDouble(s);
}




static int isAndroid_flag;

static boolean isAndroid() {
  if (isAndroid_flag == 0)
    isAndroid_flag = System.getProperty("java.vendor").toLowerCase().indexOf("android") >= 0 ? 1 : -1;
  return isAndroid_flag > 0;
}



static Boolean isHeadless_cache;

static boolean isHeadless() {
  if (isHeadless_cache != null) return isHeadless_cache;
  if (isAndroid()) return isHeadless_cache = true;
  if (GraphicsEnvironment.isHeadless()) return isHeadless_cache = true;
  
  // Also check if AWT actually works.
  // If DISPLAY variable is set but no X server up, this will notice.
  
  try {
    SwingUtilities.isEventDispatchThread();
    return isHeadless_cache = false;
  } catch (Throwable e) { return isHeadless_cache = true; }
}


static List<VF1<Map>> _threadInfo_makers = synchroList();

static Object _threadInfo() {
  if (empty(_threadInfo_makers)) return null;
  HashMap map = new HashMap();
  pcallFAll(_threadInfo_makers, map);
  return map;
}


static Runnable asRunnable(Object o) {
  return toRunnable(o);
}




static void _inheritThreadInfo(Object info) {
  _threadInheritInfo(info);
}


static List<Pair> _registerDangerousWeakMap_preList;

static <A> A _registerDangerousWeakMap(A map) {
  return _registerDangerousWeakMap(map, null);
}

static <A> A _registerDangerousWeakMap(A map, Object init) {
  
  callF(init, map);
  
  if (init instanceof String) {
    final String f =  (String) init;
    init = new VF1<Map>() { public void get(Map map) { try {  callMC(f, map) ; } catch (Exception __e) { throw rethrow(__e); } }
  public String toString() { return "callMC(f, map)"; }};
  }
    
  if (javax() == null) {
    // We're in class init
    if (_registerDangerousWeakMap_preList == null) _registerDangerousWeakMap_preList = synchroList();
    _registerDangerousWeakMap_preList.add(pair(map, init));
    return map;
  }
  
  call(javax(), "_registerDangerousWeakMap", map, init);
  
  return map;
}

static void _onLoad_registerDangerousWeakMap() {
  
  assertNotNull(javax());
  if (_registerDangerousWeakMap_preList == null) return;
  for (Pair p : _registerDangerousWeakMap_preList)
    _registerDangerousWeakMap(p.a, p.b);
  _registerDangerousWeakMap_preList = null;
  
}


static Map synchroMap() {
  return synchroHashMap();
}

static <A, B> Map<A, B> synchroMap(Map<A, B> map) {
  
  
    return Collections.synchronizedMap(map);
  
}


static Throwable getExceptionCause(Throwable e) {
  Throwable c = e.getCause();
  return c != null ? c : e;
}


static String joinWithSpace(Iterable c) {
  return join(" ", c);
}

static String joinWithSpace(String... c) {
  return join(" ", c);
}



static volatile StringBuffer local_log = new StringBuffer(); // not redirected




static boolean printAlsoToSystemOut = true;

static volatile Appendable print_log = local_log; // might be redirected, e.g. to main bot

// in bytes - will cut to half that
static volatile int print_log_max = 1024*1024;
static volatile int local_log_max = 100*1024;

static boolean print_silent = false; // total mute if set

static Object print_byThread_lock = new Object();
static volatile ThreadLocal<Object> print_byThread; // special handling by thread - prefers F1<S, Bool>
static volatile Object print_allThreads;
static volatile Object print_preprocess;

static void print() {
  print("");
}

static <A> A print(String s, A o) {
  print(combinePrintParameters(s, o));
  return o;
}

// slightly overblown signature to return original object...
static <A> A print(A o) {
  ping_okInCleanUp();
  if (print_silent) return o;
  String s = o + "\n";
  print_noNewLine(s);
  return o;
}

static void print_noNewLine(String s) {
  
  try {
    Object f = getThreadLocal(print_byThread_dontCreate());
    if (f == null) f = print_allThreads;
      if (f != null)
        // We do need the general callF machinery here as print_byThread is sometimes shared between modules
        if (isFalse(
          
            f instanceof F1 ? ((F1) f).get(s) :
          
          callF(f, s))) return;
  } catch (Throwable e) {
    System.out.println(getStackTrace(e));
  }
  

  print_raw(s);
}

static void print_raw(String s) {
  
  if (print_preprocess != null) s = (String) callF(print_preprocess, s);
  s = fixNewLines(s);
  
  Appendable loc = local_log;
  Appendable buf = print_log;
  int loc_max = print_log_max;
  if (buf != loc && buf != null) {
    print_append(buf, s, print_log_max);
    loc_max = local_log_max;
  }
  if (loc != null) 
    print_append(loc, s, loc_max);
  
  
  if (printAlsoToSystemOut)
    System.out.print(s);
  
  
  vmBus_send("printed", mc(), s);
  
}

static void print_autoRotate() {
  
}


static boolean isInstanceX(Class type, Object arg) {
  if (type == boolean.class) return arg instanceof Boolean;
  if (type == int.class) return arg instanceof Integer;
  if (type == long.class) return arg instanceof Long;
  if (type == float.class) return arg instanceof Float;
  if (type == short.class) return arg instanceof Short;
  if (type == char.class) return arg instanceof Character;
  if (type == byte.class) return arg instanceof Byte;
  if (type == double.class) return arg instanceof Double;
  return type.isInstance(arg);
}


static void vmBus_send(String msg, Object... args) {
  Object arg = vmBus_wrapArgs(args);
  pcallFAll_minimalExceptionHandling(vm_busListeners_live(), msg, arg);
  pcallFAll_minimalExceptionHandling(vm_busListenersByMessage_live().get(msg), msg, arg);
}

static void vmBus_send(String msg) {
  vmBus_send(msg, (Object) null);
}


static boolean methodIsStatic(Method m) {
  return (m.getModifiers() & Modifier.STATIC) != 0;
}


static boolean argumentCompatibleWithType(Object arg, Class type) {
  return arg == null ? !type.isPrimitive() : isInstanceX(type, arg);
}


static void arraycopy(Object[] a, Object[] b) {
  if (a != null && b != null)
    arraycopy(a, 0, b, 0, Math.min(a.length, b.length));
}

static void arraycopy(Object src, int srcPos, int destPos, int n) { arraycopy(src, srcPos, src, destPos, n); }
static void arraycopy(Object src, int srcPos, Object dest, int destPos, int n) {
  if (n != 0)
    System.arraycopy(src, srcPos, dest, destPos, n);
}


public static <A> String join(String glue, Iterable<A> strings) {
  if (strings == null) return "";
  if (strings instanceof Collection) {
    if (((Collection) strings).size() == 1) return str(first((Collection) strings));
  }
  StringBuilder buf = new StringBuilder();
  Iterator<A> i = strings.iterator();
  if (i.hasNext()) {
    buf.append(i.next());
    while (i.hasNext())
      buf.append(glue).append(i.next());
  }
  return buf.toString();
}

public static String join(String glue, String... strings) {
  return join(glue, Arrays.asList(strings));
}

public static String join(String glue, Object... strings) {
  return join(glue, Arrays.asList(strings));
}

static <A> String join(Iterable<A> strings) {
  return join("", strings);
}

static <A> String join(Iterable<A> strings, String glue) {
  return join(glue, strings);
}

public static String join(String[] strings) {
  return join("", strings);
}


static String join(String glue, Pair p) {
  return p == null ? "" : str(p.a) + glue + str(p.b);
}



static List<String> getClassNames(Collection l) {
  List<String> out = new ArrayList();
  if (l != null) for (Object o : l)
    out.add(o == null ? null : getClassName(o));
  return out;
}




static WeakHasherMap<Symbol, Boolean> symbol_map = new WeakHasherMap(new Hasher<Symbol>() {
  public int hashCode(Symbol symbol) { return symbol.text.hashCode(); }
  public boolean equals(Symbol a, Symbol b) {
    if (a == null) return b == null;
    return b != null && eq(a.text, b.text);
  }
});



static Symbol symbol(String s) {
  
  
  if (s == null) return null;
  synchronized(symbol_map) {
    // TODO: avoid object creation by passing the string to findKey
    Symbol symbol = new Symbol(s, true);
    Symbol existingSymbol = symbol_map.findKey(symbol);
    if (existingSymbol == null)
      symbol_map.put(existingSymbol = symbol, true);
    
      
    return existingSymbol;
  }
  
}

static Symbol symbol(CharSequence s) {
  if (s == null) return null;
  
  
  if (s instanceof Symbol) return (Symbol) s;
  if (s instanceof String) return symbol((String) s);
  return symbol(str(s));
  
}

static Symbol symbol(Object o) {
  return symbol((CharSequence) o);
}




static AutoCloseable tempInterceptPrintIfNotIntercepted(F1<String, Boolean> f) {
  return print_byThread().get() == null ? tempInterceptPrint(f) : null;
}


static <A> List<A> synchroList() {
  return synchroList(new ArrayList<A>());
}

static <A> List<A> synchroList(List<A> l) {
  
  
    return Collections.synchronizedList(l);
  
}



static void pcallFAll(Collection l, Object... args) {
  if (l != null) for (Object f : cloneList(l)) pcallF(f, args);
}

static void pcallFAll(Iterator it, Object... args) {
  while (it.hasNext()) pcallF(it.next(), args);
}


static Runnable toRunnable(final Object o) {
  if (o == null) return null;
  if (o instanceof Runnable) return (Runnable) o;
  
  if (o instanceof String) throw fail("callF_legacy");
  
  return new Runnable() {  public void run() { try {  callF(o) ;
} catch (Exception __e) { throw rethrow(__e); } }  public String toString() { return "callF(o)"; }};
}


static List<VF1<Map>> _threadInheritInfo_retrievers = synchroList();

static void _threadInheritInfo(Object info) {
  if (info == null) return;
  pcallFAll(_threadInheritInfo_retrievers, (Map) info);
}


static HashMap<String, List<Method>> callMC_cache = new HashMap();
static String callMC_key;
static Method callMC_value;

// varargs assignment fixer for a single string array argument
static Object callMC(String method, String[] arg) {
  return callMC(method, new Object[] {arg});
}

static Object callMC(String method, Object... args) { try {
  Method me;
  if (callMC_cache == null) callMC_cache = new HashMap(); // initializer time workaround
  synchronized(callMC_cache) {
    me = method == callMC_key ? callMC_value : null;
  }
  if (me != null) try {
    return invokeMethod(me, null, args);
  } catch (IllegalArgumentException e) {
    throw new RuntimeException("Can't call " + me + " with arguments " + classNames(args), e);
  }

  List<Method> m;
  synchronized(callMC_cache) {
    m = callMC_cache.get(method);
  }
  if (m == null) {
    if (callMC_cache.isEmpty()) {
      callMC_makeCache();
      m = callMC_cache.get(method);
    }
    if (m == null) throw fail("Method named " + method + " not found in main");
  }
  int n = m.size();
  if (n == 1) {
    me = m.get(0);
    synchronized(callMC_cache) {
      callMC_key = method;
      callMC_value = me;
    }
    try {
      return invokeMethod(me, null, args);
    } catch (IllegalArgumentException e) {
      throw new RuntimeException("Can't call " + me + " with arguments " + classNames(args), e);
    }
  }
  for (int i = 0; i < n; i++) {
    me = m.get(i);
    if (call_checkArgs(me, args, false))
      return invokeMethod(me, null, args);
  }
  throw fail("No method called " + method + " with arguments (" + joinWithComma(getClasses(args)) + ") found in main");
} catch (Exception __e) { throw rethrow(__e); } }

static void callMC_makeCache() {
  synchronized(callMC_cache) {
    callMC_cache.clear();
    Class _c = (Class) mc(), c = _c;
    while (c != null) {
      for (Method m : c.getDeclaredMethods())
        if ((m.getModifiers() & java.lang.reflect.Modifier.STATIC) != 0) {
          makeAccessible(m);
          multiMapPut(callMC_cache, m.getName(), m);
        }
      c = c.getSuperclass();
    }
  }
}


static Class javax() {
  return getJavaX();
}


static <A, B> Pair<A, B> pair(A a, B b) {
  return new Pair(a, b);
}

static <A> Pair<A, A> pair(A a) {
  return new Pair(a, a);
}


static <A> A assertNotNull(A a) {
  assertTrue(a != null);
  return a;
}

static <A> A assertNotNull(String msg, A a) {
  assertTrue(msg, a != null);
  return a;
}




static Map synchroHashMap() {
  return synchronizedMap(new HashMap());
}



static String combinePrintParameters(String s, Object o) {
  return (endsWithLetterOrDigit(s) ? s + ": " : s) + o;
}


static void ping_okInCleanUp() {


  if (ping_pauseAll || ping_anyActions)
    ping_impl(true);


}


// this syntax should be removed...
static Object getThreadLocal(Object o, String name) {
  ThreadLocal t =  (ThreadLocal) (getOpt(o, name));
  return t != null ? t.get() : null;
}

static <A> A getThreadLocal(ThreadLocal<A> tl) {
  return tl == null ? null : tl.get();
}

static <A> A getThreadLocal(ThreadLocal<A> tl, A defaultValue) {
  return or(getThreadLocal(tl), defaultValue);
}


static ThreadLocal<Object> print_byThread_dontCreate() {
  return print_byThread;
}


static boolean isFalse(Object o) {
  return eq(false, o);
}


static String getStackTrace(Throwable throwable) {
  lastException(throwable);
  return getStackTrace_noRecord(throwable);
}

static String getStackTrace_noRecord(Throwable throwable) {
  StringWriter writer = new StringWriter();
  throwable.printStackTrace(new PrintWriter(writer));
  return hideCredentials(writer.toString());
}

static String getStackTrace() {
  return getStackTrace_noRecord(new Throwable());
}

static String getStackTrace(String msg) {
  return getStackTrace_noRecord(new Throwable(msg));
}


static String fixNewLines(String s) {
  int i = indexOf(s, '\r');
  if (i < 0) return s;
  int l = s.length();
  StringBuilder out = new StringBuilder(l);
  out.append(s, 0, i);
  for (; i < l; i++) {
    char c = s.charAt(i);
    if (c != '\r')
      out.append(c);
    else {
      out.append('\n');
      if (i+1 < l && s.charAt(i+1) == '\n') ++i;
    }
  }
  return out.toString();
}


static void print_append(Appendable buf, String s, int max) { try {
  synchronized(buf) {
    buf.append(s);
    if (buf instanceof StringBuffer)
      rotateStringBuffer(((StringBuffer) buf), max);
    else if (buf instanceof StringBuilder)
      rotateStringBuilder(((StringBuilder) buf), max);
  }
} catch (Exception __e) { throw rethrow(__e); } }


static Class mc() {
  return main.class;
}


static Object vmBus_wrapArgs(Object... args) {
  return empty(args) ? null
    : l(args) == 1 ? args[0]
    : args;
}


static void pcallFAll_minimalExceptionHandling(Collection l, Object... args) {
  if (l != null) for  (Object f : cloneList(l)) { ping(); pcallF_minimalExceptionHandling(f, args); }
}

static void pcallFAll_minimalExceptionHandling(Iterator it, Object... args) {
  while  (it.hasNext()) { ping(); pcallF_minimalExceptionHandling(it.next(), args); }
}


static Set vm_busListeners_live_cache;
static Set vm_busListeners_live() { if (vm_busListeners_live_cache == null) vm_busListeners_live_cache = vm_busListeners_live_load(); return vm_busListeners_live_cache;}

static Set vm_busListeners_live_load() {
  return vm_generalIdentityHashSet("busListeners");
}


static Map<String, Set> vm_busListenersByMessage_live_cache;
static Map<String, Set> vm_busListenersByMessage_live() { if (vm_busListenersByMessage_live_cache == null) vm_busListenersByMessage_live_cache = vm_busListenersByMessage_live_load(); return vm_busListenersByMessage_live_cache;}

static Map<String, Set> vm_busListenersByMessage_live_load() {
  return vm_generalHashMap("busListenersByMessage");
}



static Object first(Object list) {
  return first((Iterable) list);
}


static <A> A first(List<A> list) {
  return empty(list) ? null : list.get(0);
}

static <A> A first(A[] bla) {
  return bla == null || bla.length == 0 ? null : bla[0];
}

static <A, B> Pair<A, B> first(Map<A, B> map) {
  return mapEntryToPair(first(entrySet(map)));
}

static <A, B> Pair<A, B> first(MultiMap<A, B> mm) {
  if (mm == null) return null;
  var e = first(mm.data.entrySet());
  if (e == null) return null;
  return pair(e.getKey(), first(e.getValue()));
}


static <A> A first(IterableIterator<A> i) {
  return first((Iterator<A>) i);
}


static <A> A first(Iterator<A> i) {
  return i == null || !i.hasNext() ? null : i.next();
}

static <A> A first(Iterable<A> i) {
  if (i == null) return null;
  Iterator<A> it = i.iterator();
  return it.hasNext() ? it.next() : null;
}

static Character first(String s) { return empty(s) ? null : s.charAt(0); }
static Character first(CharSequence s) { return empty(s) ? null : s.charAt(0); }


static <A, B> A first(Pair<A, B> p) {
  return p == null ? null : p.a;
}




static Byte first(byte[] l) { 
  return empty(l) ? null : l[0];
}





static <A> A first(A[] l, IF1<A, Boolean> pred) {
  return firstThat(l, pred);
}

static <A> A first(Iterable<A> l, IF1<A, Boolean> pred) {
  return firstThat(l, pred);
}

static <A> A first(IF1<A, Boolean> pred, Iterable<A> l) {
  return firstThat(pred, l);
}







static ThreadLocal<Object> print_byThread() {
  synchronized(print_byThread_lock) {
    if (print_byThread == null)
      print_byThread = new ThreadLocal();
  }
  return print_byThread;
}


// f can return false to suppress regular printing
// call print_raw within f to actually print something
static AutoCloseable tempInterceptPrint(F1<String, Boolean> f) {
  return tempSetThreadLocal(print_byThread(), f);
}


static <A> ArrayList<A> cloneList(Iterable<A> l) {
  return l instanceof Collection ? cloneList((Collection) l) : asList(l);
}

static <A> ArrayList<A> cloneList(Collection<A> l) {
  if (l == null) return new ArrayList();
  synchronized(collectionMutex(l)) {
    return new ArrayList<A>(l);
  }
}


static Object pcallF(Object f, Object... args) {
  return pcallFunction(f, args);
}


static <A> A pcallF(F0<A> f) {
  try { return f == null ? null : f.get(); } catch (Throwable __e) { printStackTrace(__e); } return null;
}



static <A, B> B pcallF(F1<A, B> f, A a) {
  try { return f == null ? null : f.get(a); } catch (Throwable __e) { printStackTrace(__e); } return null;
}



static <A> void pcallF(VF1<A> f, A a) {
  try {
    { if (f != null) f.get(a); }
  } catch (Throwable __e) { printStackTrace(__e); }
}


static Object pcallF(Runnable r) {
  try { { if (r != null) r.run(); } } catch (Throwable __e) { printStackTrace(__e); } return null;
}

static <A> A pcallF(IF0<A> f) {
  try { return f == null ? null : f.get(); } catch (Throwable __e) { printStackTrace(__e); } return null;
}

static <A, B> B pcallF(IF1<A, B> f, A a) {
  try { return f == null ? null : f.get(a); } catch (Throwable __e) { printStackTrace(__e); } return null;
}



static List<Class> getClasses(Object[] array) {
  List<Class> l = emptyList(l(array));
  for (Object o : array) l.add(_getClass(o));
  return l;
}


static <A, B> void multiMapPut(Map<A, List<B>> map, A a, B b) {
  List<B> l = map.get(a);
  if (l == null)
    map.put(a, l = new ArrayList());
  l.add(b);
}


static <A, B> void multiMapPut(MultiMap<A, B> mm, A key, B value) {
  if (mm != null && key != null && value != null) mm.put(key, value);
}



static Class __javax;

static Class getJavaX() { try {
  
  return __javax;
} catch (Exception __e) { throw rethrow(__e); } }

static void __setJavaX(Class j) {
  __javax = j;
  _onJavaXSet();
}


static void assertTrue(Object o) {
  if (!(eq(o, true) /*|| isTrue(pcallF(o))*/))
    throw fail(str(o));
}
  
static boolean assertTrue(String msg, boolean b) {
  if (!b)
    throw fail(msg);
  return b;
}

static boolean assertTrue(boolean b) {
  if (!b)
    throw fail("oops");
  return b;
}


static Map synchronizedMap() {
  return synchroMap();
}

static <A, B> Map<A, B> synchronizedMap(Map<A, B> map) {
  return synchroMap(map);
}


static boolean endsWithLetterOrDigit(String s) {
  return s != null && s.length() > 0 && Character.isLetterOrDigit(s.charAt(s.length()-1));
}








//sbool ping_actions_shareable = true;
static volatile boolean ping_pauseAll = false;
static int ping_sleep = 100; // poll pauseAll flag every 100
static volatile boolean ping_anyActions = false;
static Map<Thread, Object> ping_actions = newWeakHashMap();
static ThreadLocal<Boolean> ping_isCleanUpThread = new ThreadLocal();

// always returns true
static boolean ping() {
  //ifdef useNewPing
  newPing();
  //endifdef
  if (ping_pauseAll || ping_anyActions) ping_impl(true /* XXX */);
  //ifndef LeanMode ping_impl(); endifndef
  return true;
}

// returns true when it slept
static boolean ping_impl(boolean okInCleanUp) { try {
  if (ping_pauseAll && !isAWTThread()) {
    do
      Thread.sleep(ping_sleep);
    while (ping_pauseAll);
    return true;
  }
  
  if (ping_anyActions) { // don't allow sharing ping_actions
    if (!okInCleanUp && !isTrue(ping_isCleanUpThread.get()))
      failIfUnlicensed();
    Object action = null;
    synchronized(ping_actions) {
      if (!ping_actions.isEmpty()) {
        action = ping_actions.get(currentThread());
        if (action instanceof Runnable)
          ping_actions.remove(currentThread());
        if (ping_actions.isEmpty()) ping_anyActions = false;
      }
    }
    
    if (action instanceof Runnable)
      ((Runnable) action).run();
    else if (eq(action, "cancelled"))
      throw fail("Thread cancelled.");
  }

  return false;
} catch (Exception __e) { throw rethrow(__e); } }




static Object getOpt(Object o, String field) {
  return getOpt_cached(o, field);
}

static Object getOpt(String field, Object o) {
  return getOpt_cached(o, field);
}

static Object getOpt_raw(Object o, String field) { try {
  Field f = getOpt_findField(o.getClass(), field);
  if (f == null) return null;
  makeAccessible(f);
  return f.get(o);
} catch (Exception __e) { throw rethrow(__e); } }

// access of static fields is not yet optimized
static Object getOpt(Class c, String field) { try {
  if (c == null) return null;
  Field f = getOpt_findStaticField(c, field);
  if (f == null) return null;
  makeAccessible(f);
  return f.get(null);
} catch (Exception __e) { throw rethrow(__e); } }

static Field getOpt_findStaticField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field) && (f.getModifiers() & java.lang.reflect.Modifier.STATIC) != 0)
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  return null;
}



static <A> A or(A a, A b) {
  return a != null ? a : b;
}


// PersistableThrowable doesn't hold GC-disturbing class references in backtrace
static volatile PersistableThrowable lastException_lastException;

static PersistableThrowable lastException() {
  return lastException_lastException;
}

static void lastException(Throwable e) {
  lastException_lastException = persistableThrowable(e);
}


static String hideCredentials(URL url) { return url == null ? null : hideCredentials(str(url)); }

static String hideCredentials(String url) {
  try {
    if (startsWithOneOf(url, "http://", "https://") && isAGIBlueDomain(hostNameFromURL(url))) return url;
  } catch (Throwable e) {
    print("HideCredentials", e);
  }
  return url.replaceAll("([&?])(_pass|key|cookie)=[^&\\s\"]*", "$1$2=<hidden>");
}

static String hideCredentials(Object o) {
  return hideCredentials(str(o));
}


static <A> int indexOf(List<A> l, A a, int startIndex) {
  if (l == null) return -1;
  int n = l(l);
  for (int i = startIndex; i < n; i++)
    if (eq(l.get(i), a))
      return i;
  return -1;
}

static <A> int indexOf(List<A> l, int startIndex, A a) {
  return indexOf(l, a, startIndex);
}

static <A> int indexOf(List<A> l, A a) {
  if (l == null) return -1;
  return l.indexOf(a);
}

static int indexOf(String a, String b) {
  return a == null || b == null ? -1 : a.indexOf(b);
}

static int indexOf(String a, String b, int i) {
  return a == null || b == null ? -1 : a.indexOf(b, i);
}

static int indexOf(String a, char b) {
  return a == null ? -1 : a.indexOf(b);
}

static int indexOf(String a, int i, char b) {
  return indexOf(a, b, i);
}

static int indexOf(String a, char b, int i) {
  return a == null ? -1 : a.indexOf(b, i);
}

static int indexOf(String a, int i, String b) {
  return a == null || b == null ? -1 : a.indexOf(b, i);
}

static <A> int indexOf(A[] x, A a) {
  int n = l(x);
  for (int i = 0; i < n; i++)
    if (eq(x[i], a))
      return i;
  return -1;
}

static <A> int indexOf(Iterable<A> l, A a) {
  if (l == null) return -1;
  int i = 0;
  for (A x : l) {
    if (eq(x, a))
      return i;
    i++;
  }
  return -1;
}



static void rotateStringBuffer(StringBuffer buf, int max) { try {
  if (buf == null) return;
  synchronized(buf) {
    if (buf.length() <= max) return;
    
    try {
      int newLength = max/2;
      int ofs = buf.length()-newLength;
      String newString = buf.substring(ofs);
      buf.setLength(0);
      buf.append("[...] ").append(newString);
    } catch (Exception e) {
      buf.setLength(0);
    }
    buf.trimToSize();
  }
} catch (Exception __e) { throw rethrow(__e); } }


static void rotateStringBuilder(StringBuilder buf, int max) { try {
  if (buf == null) return;
  synchronized(buf) {
    if (buf.length() <= max) return;
    
    try {
      int newLength = max/2;
      int ofs = buf.length()-newLength;
      String newString = buf.substring(ofs);
      buf.setLength(0);
      buf.append("[...] ").append(newString);
    } catch (Exception e) {
      buf.setLength(0);
    }
    buf.trimToSize();
  }
} catch (Exception __e) { throw rethrow(__e); } }


static Object pcallF_minimalExceptionHandling(Object f, Object... args) {
  try {
    return callFunction(f, args);
  } catch (Throwable e) {
    System.out.println(getStackTrace(e));
    _storeException(e);
  }
  return null;
}


static Set vm_generalIdentityHashSet(Object name) {
  synchronized(vm_generalMap()) {
    Set set =  (Set) (vm_generalMap_get(name));
    if (set == null)
      vm_generalMap_put(name, set = syncIdentityHashSet());
    return set;
  }
}



static Map vm_generalHashMap(Object name) {
  synchronized(vm_generalMap()) {
    Map m =  (Map) (vm_generalMap_get(name));
    if (m == null)
      vm_generalMap_put(name, m = syncHashMap());
    return m;
  }
}



static <A, B> Pair<A, B> mapEntryToPair(Map.Entry<A, B> e) {
  return e == null ? null : pair(e.getKey(), e.getValue());
}


static <A, B> Set<Map.Entry<A,B>> entrySet(Map<A, B> map) {
  return _entrySet(map);
}


static <A> A firstThat(Iterable<A> l, IF1<A, Boolean> pred) {
  for (A a : unnullForIteration(l))
    if (pred.get(a))
      return a;
  return null;
}

static <A> A firstThat(A[] l, IF1<A, Boolean> pred) {
  for (A a : unnullForIteration(l))
    if (pred.get(a))
      return a;
  return null;
}

static <A> A firstThat(IF1<A, Boolean> pred, Iterable<A> l) {
  return firstThat(l, pred);
}

static <A> A firstThat(IF1<A, Boolean> pred, A[] l) {
  return firstThat(l, pred);
}





static <A> AutoCloseable tempSetThreadLocal(final ThreadLocal<A> tl, A a) {
  if (tl == null) return null;
  final A prev = setThreadLocal(tl, a);
  return new AutoCloseable() { public String toString() { return "tl.set(prev);"; } public void close() throws Exception { tl.set(prev); }};
}


// TODO: JDK 17!! ?? No! Yes? Yes!!

static Object collectionMutex(List l) {
  return l;
}

static Object collectionMutex(Object o) {
  

  if (o instanceof List) return o;
  
  // TODO: actually use our own maps so we can get the mutex properly
  
  String c = className(o);
  
    
  
    
  
  return o;
}


static Object pcallFunction(Object f, Object... args) {
  try { return callFunction(f, args); } catch (Throwable __e) { printStackTrace(__e); }
  return null;
}


static <A extends Throwable> A printStackTrace(A e) {
  // we go to system.out now - system.err is nonsense
  if (e != null) print(getStackTrace(e));
  return e;
}

static void printStackTrace() {
  printStackTrace(new Throwable());
}

static void printStackTrace(String msg) {
  printStackTrace(new Throwable(msg));
}

static void printStackTrace(String msg, Throwable e) {
  printStackTrace(new Throwable(msg, e));
}


static Class<?> _getClass(String name) {
  try {
    return Class.forName(name);
  } catch (ClassNotFoundException e) {
    return null; // could optimize this
  }
}

static Class _getClass(Object o) {
  return o == null ? null
    : o instanceof Class ? (Class) o : o.getClass();
}

static Class _getClass(Object realm, String name) {
  try {
    return classLoaderForObject(realm).loadClass(classNameToVM(name));
  } catch (ClassNotFoundException e) {
    return null; // could optimize this
  }
}


static void _onJavaXSet() {}


static <A, B> Map<A, B> newWeakHashMap() {
  return _registerWeakMap(synchroMap(new WeakHashMap()));
}


static void newPing() {
  var tl = newPing_actionTL();
  Runnable action = tl == null ? null : tl.get();
  { if (action != null) action.run(); }
}


static boolean isTrue(Object o) {
  if (o instanceof Boolean)
    return ((Boolean) o).booleanValue();
  if (o == null) return false;
  if (o instanceof ThreadLocal) // TODO: remove this
    return isTrue(((ThreadLocal) o).get());
  throw fail(getClassName(o));
}

static boolean isTrue(Boolean b) {
  return b != null && b.booleanValue();
}


static void failIfUnlicensed() {
  assertTrue("license off", licensed());
}


static Thread currentThread() {
  return Thread.currentThread();
}


//static final Map<Class, HashMap<S, Field>> getOpt_cache = newDangerousWeakHashMap(f getOpt_special_init);

static class getOpt_Map extends WeakHashMap {
  getOpt_Map() {
    if (getOpt_special == null) getOpt_special = new HashMap();
    clear();
  }
  
  public void clear() {
    super.clear();
    //print("getOpt clear");
    put(Class.class, getOpt_special);
    put(String.class, getOpt_special);
  }
}

static final Map<Class, HashMap<String, Field>> getOpt_cache = _registerDangerousWeakMap(synchroMap(new getOpt_Map()));
//static final Map<Class, HashMap<S, Field>> getOpt_cache = _registerWeakMap(synchroMap(new getOpt_Map));
static HashMap getOpt_special; // just a marker

/*static void getOpt_special_init(Map map) {
  map.put(Class.class, getOpt_special);
  map.put(S.class, getOpt_special);
}*/

static Map<String, Field> getOpt_getFieldMap(Object o) {
  Class c = _getClass(o);
  HashMap<String, Field> map = getOpt_cache.get(c);
  if (map == null)
    map = getOpt_makeCache(c);
  return map;
}

static Object getOpt_cached(Object o, String field) { try {
  if (o == null) return null;

  Map<String, Field> map = getOpt_getFieldMap(o);

  if (map == getOpt_special) {
    if (o instanceof Class)
      return getOpt((Class) o, field);
    /*if (o instanceof S)
      ret getOpt(getBot((S) o), field);*/
    if (o instanceof Map)
      return ((Map) o).get(field);
  }
    
  Field f = map.get(field);
  if (f != null) return f.get(o);
  
    if (o instanceof DynamicObject)
      return syncMapGet2(((DynamicObject) o).fieldValues, field);
  
  return null;
} catch (Exception __e) { throw rethrow(__e); } }

// used internally - we are in synchronized block
static HashMap<String, Field> getOpt_makeCache(Class c) {
  HashMap<String, Field> map;
  if (isSubtypeOf(c, Map.class))
    map = getOpt_special;
  else {
    map = new HashMap();
    if (!reflection_classesNotToScan().contains(c.getName())) {
      Class _c = c;
      do {
        for (Field f : _c.getDeclaredFields()) {
          makeAccessible(f);
          String name = f.getName();
          if (!map.containsKey(name))
            map.put(name, f);
        }
        _c = _c.getSuperclass();
      } while (_c != null);
    }
  }
  if (getOpt_cache != null) getOpt_cache.put(c, map);
  return map;
}


static Field getOpt_findField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field))
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  return null;
}


static PersistableThrowable persistableThrowable(Throwable e) {
  return e == null ? null : new PersistableThrowable(e);
}


static boolean startsWithOneOf(String s, String... l) {
  for (String x : l) if (startsWith(s, x)) return true; return false;
}

static boolean startsWithOneOf(String s, Matches m, String... l) {
  for (String x : l) if (startsWith(s, x, m)) return true; return false;
}


static boolean isAGIBlueDomain(String domain) {
  return domainIsUnder(domain, theAGIBlueDomain());
}


static String hostNameFromURL(String url) { try {
  return empty(url) ? null : new URL(url).getHost();
} catch (Exception __e) { throw rethrow(__e); } }


static Object callFunction(Object f, Object... args) {
  return callF(f, args);
}


static Throwable _storeException_value;

static void _storeException(Throwable e) {
  _storeException_value = e;
}


static Map vm_generalMap_map;

static Map vm_generalMap() {
  if (vm_generalMap_map == null)
    
    
    
    vm_generalMap_map = (Map) get(javax(), "generalMap");
    
    
  return vm_generalMap_map;
}


static Object vm_generalMap_get(Object key) {
  return vm_generalMap().get(key);
}


static Object vm_generalMap_put(Object key, Object value) {
  return mapPutOrRemove(vm_generalMap(), key, value);
}


static <A> Set<A> syncIdentityHashSet() {
  return (Set) synchronizedSet(identityHashSet());
}


static Map syncHashMap() {
  return synchroHashMap();
}


static <A, B> Set<Map.Entry<A,B>> _entrySet(Map<A, B> map) {
  return map == null ? Collections.EMPTY_SET : map.entrySet();
}


static String unnullForIteration(String s) {
  return s == null ? "" : s;
}

static <A> Collection<A> unnullForIteration(Collection<A> l) {
  return l == null ? immutableEmptyList() : l;
}

static <A> List<A> unnullForIteration(List<A> l) { return l == null ? immutableEmptyList() : l; }
static int[] unnullForIteration(int[] l) { return l == null ? emptyIntArray() : l; }
static char[] unnullForIteration(char[] l) { return l == null ? emptyCharArray() : l; }
static double[] unnullForIteration(double[] l) { return l == null ? emptyDoubleArray() : l; }
static short[] unnullForIteration(short[] l) { return l == null ? emptyShortArray() : l; }

static <A, B> Map<A, B> unnullForIteration(Map<A, B> l) {
  return l == null ? immutableEmptyMap() : l;
}

static <A> Iterable<A> unnullForIteration(Iterable<A> i) {
  return i == null ? immutableEmptyList() : i;
}

static <A> A[] unnullForIteration(A[] a) {
  return a == null ? (A[]) emptyObjectArray() : a;
}

static BitSet unnullForIteration(BitSet b) {
  return b == null ? new BitSet() : b;
}


static Pt unnullForIteration(Pt p) {
  return p == null ? new Pt() : p;
}


//ifclass Symbol

static Symbol unnullForIteration(Symbol s) {
  return s == null ? emptySymbol() : s;
}
//endif



static <A, B> Pair<A, B> unnullForIteration(Pair<A, B> p) {
  return p != null ? p : new Pair(null, null);
}


static long unnullForIteration(Long l) { return l == null ? 0L : l; }




static <A> A setThreadLocal(ThreadLocal<A> tl, A value) {
  if (tl == null) return null;
  A old = tl.get();
  tl.set(value);
  return old;
}


static String className(Object o) {
  return getClassName(o);
}


static ClassLoader classLoaderForObject(Object o) {
  if (o instanceof ClassLoader) return ((ClassLoader) o);
  if (o == null) return null;
  return _getClass(o).getClassLoader();
}


// Note: This is actually broken. Inner classes must stay with a $ separator
static String classNameToVM(String name) {
  return name.replace(".", "$");
}


static List _registerWeakMap_preList;

static <A> A _registerWeakMap(A map) {
  if (javax() == null) {
    // We're in class init
    if (_registerWeakMap_preList == null) _registerWeakMap_preList = synchroList();
    _registerWeakMap_preList.add(map);
    return map;
  }
  
  try {
    call(javax(), "_registerWeakMap", map);
  } catch (Throwable e) {
    printException(e);
    print("Upgrade JavaX!!");
  }
  return map;
}

static void _onLoad_registerWeakMap() {
  assertNotNull(javax());
  if (_registerWeakMap_preList == null) return;
  for (Object o : _registerWeakMap_preList)
    _registerWeakMap(o);
  _registerWeakMap_preList = null;
}


static x30_pkg.x30_util.BetterThreadLocal<Runnable> newPing_actionTL;

static x30_pkg.x30_util.BetterThreadLocal<Runnable> newPing_actionTL() {
  if (newPing_actionTL == null)
    newPing_actionTL = vm_generalMap_getOrCreate("newPing_actionTL",
      () -> {
        Runnable value =  (Runnable) (callF_gen(vm_generalMap_get("newPing_valueForNewThread")));
        var tl = new x30_pkg.x30_util.BetterThreadLocal<Runnable>();
        tl.set(value);
        return tl;
      });
  return newPing_actionTL;
}



static volatile boolean licensed_yes = true;

static boolean licensed() {
  if (!licensed_yes) return false;
  ping_okInCleanUp();
  return true;
}

static void licensed_off() {
  licensed_yes = false;
}


static void clear(Collection c) {
  if (c != null) c.clear();
}

static void clear(Map map) {
  if (map != null) map.clear();
}


static <A, B> void put(Map<A, B> map, A a, B b) {
  if (map != null) map.put(a, b);
}

static <A> void put(List<A> l, int i, A a) {
  if (l != null && i >= 0 && i < l(l)) l.set(i, a);
}


static <A, B> B syncMapGet2(Map<A, B> map, A a) {
  if (map == null) return null;
  synchronized(collectionMutex(map)) {
    return map.get(a);
  }
}

static <A, B> B syncMapGet2(A a, Map<A, B> map) {
  return syncMapGet2(map, a);
}


static boolean isSubtypeOf(Class a, Class b) {
  return a != null && b != null && b.isAssignableFrom(a); // << always hated that method, let's replace it!
}


static Set<String> reflection_classesNotToScan_value = litset(
  "jdk.internal.loader.URLClassPath"
);

static Set<String> reflection_classesNotToScan() {
  return reflection_classesNotToScan_value;
}


static boolean startsWith(String a, String b) {
  return a != null && a.startsWith(unnull(b));
}

static boolean startsWith(String a, char c) {
  return nemptyString(a) && a.charAt(0) == c;
}


  static boolean startsWith(String a, String b, Matches m) {
    if (!startsWith(a, b)) return false;
    if (m != null) m.m = new String[] {substring(a, strL(b))};
    return true;
  }


static boolean startsWith(List a, List b) {
  if (a == null || listL(b) > listL(a)) return false;
  for (int i = 0; i < listL(b); i++)
    if (neq(a.get(i), b.get(i)))
      return false;
  return true;
}




static boolean domainIsUnder(String domain, String mainDomain) {
  return eqic(domain, mainDomain) || ewic(domain, "." + mainDomain);
}


static String theAGIBlueDomain() {
  return "agi.blue";
}


// get purpose 1: access a list/array/map (safer version of x.get(y))

static <A> A get(List<A> l, int idx) {
  return l != null && idx >= 0 && idx < l(l) ? l.get(idx) : null;
}

// seems to conflict with other signatures
/*static <A, B> B get(Map<A, B> map, A key) {
  ret map != null ? map.get(key) : null;
}*/

static <A> A get(A[] l, int idx) {
  return idx >= 0 && idx < l(l) ? l[idx] : null;
}

// default to false
static boolean get(boolean[] l, int idx) {
  return idx >= 0 && idx < l(l) ? l[idx] : false;
}

// get purpose 2: access a field by reflection or a map

static Object get(Object o, String field) {
  try {
    if (o == null) return null;
    if (o instanceof Class) return get((Class) o, field);
    
    if (o instanceof Map)
      return ((Map) o).get(field);
      
    Field f = getOpt_findField(o.getClass(), field);
    if (f != null) {
      makeAccessible(f);
      return f.get(o);
    }
      
    
      if (o instanceof DynamicObject)
        return getOptDynOnly(((DynamicObject) o), field);
    
  } catch (Exception e) {
    throw asRuntimeException(e);
  }
  throw new RuntimeException("Field '" + field + "' not found in " + o.getClass().getName());
}

static Object get_raw(String field, Object o) {
  return get_raw(o, field);
}

static Object get_raw(Object o, String field) { try {
  if (o == null) return null;
  Field f = get_findField(o.getClass(), field);
  makeAccessible(f);
  return f.get(o);
} catch (Exception __e) { throw rethrow(__e); } }

static Object get(Class c, String field) {
  try {
    Field f = get_findStaticField(c, field);
    makeAccessible(f);
    return f.get(null);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
}

static Field get_findStaticField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field) && (f.getModifiers() & java.lang.reflect.Modifier.STATIC) != 0)
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  throw new RuntimeException("Static field '" + field + "' not found in " + c.getName());
}

static Field get_findField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field))
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  throw new RuntimeException("Field '" + field + "' not found in " + c.getName());
}

static Object get(String field, Object o) {
  return get(o, field);
}

static boolean get(BitSet bs, int idx) {
  return bs != null && bs.get(idx);
}


static <A, B> B mapPutOrRemove(Map<A, B> map, A key, B value) {
  if (map != null && key != null)
    if (value != null) return map.put(key, value);
    else return map.remove(key);
  return null;
}


static <A> Set<A> synchronizedSet() {
  return synchroHashSet();
}

static <A> Set<A> synchronizedSet(Set<A> set) {
  
  
    return Collections.synchronizedSet(set);
  
}


static <A> Set<A> identityHashSet() {
  return Collections.newSetFromMap(new IdentityHashMap());
}


static <A> List<A> immutableEmptyList() {
  return Collections.emptyList();
}


static short[] emptyShortArray = new short[0];
static short[] emptyShortArray() { return emptyShortArray; }


static <A, B> Map<A, B> immutableEmptyMap() {
  return Collections.emptyMap();
}




static <A extends Throwable> A printException(A e) {
  printStackTrace(e);
  return e;
}


static <A> A vm_generalMap_getOrCreate(Object key, F0<A> create) {
  return vm_generalMap_getOrCreate(key, f0ToIF0(create));
}

static <A> A vm_generalMap_getOrCreate(Object key, IF0<A> create) {
  Map generalMap = vm_generalMap();
  if (generalMap == null) return null; // must be x30 init
  
  synchronized(generalMap) { // should switch to locks here
    A a =  (A) (vm_generalMap_get(key));
    if (a == null)
      vm_generalMap_put(key, a = create == null ? null : create.get());
    return a;
  }
}




  static <A> A callF_gen(F0<A> f) {
    return f == null ? null : f.get();
  }



  static <A, B> B callF_gen(F1<A, B> f, A a) {
    return f == null ? null : f.get(a);
  }



  static <A> A callF_gen(IF0<A> f) {
    return f == null ? null : f.get();
  }



  static <A, B> B callF_gen(IF1<A, B> f, A a) {
    return f == null ? null : f.get(a);
  }


static <A, B> B callF_gen(A a, IF1<A, B> f) {
  return f == null ? null : f.get(a);
}






  static <A> void callF_gen(VF1<A> f, A a) {
    { if (f != null) f.get(a); }
  }


static <A> void callF_gen(A a, IVF1<A> f) {
  { if (f != null) f.get(a); }
}

static <A> void callF_gen(IVF1<A> f, A a) {
  { if (f != null) f.get(a); }
}

static Object callF_gen(Runnable r) { { if (r != null) r.run(); } return null; }

static Object callF_gen(Object f, Object... args) {
  return callF(f, args);
}


static <A> HashSet<A> litset(A... items) {
  return lithashset(items);
}


static boolean nemptyString(String s) {
  return s != null && s.length() > 0;
}


static String substring(String s, int x) {
  return substring(s, x, strL(s));
}

static String substring(String s, int x, int y) {
  if (s == null) return null;
  if (x < 0) x = 0;
  int n = s.length();
  if (y < x) y = x;
  if (y > n) y = n;
  if (x >= y) return "";
  return s.substring(x, y);
}



// convenience method for quickly dropping a prefix
static String substring(String s, CharSequence l) {
  return substring(s, lCharSequence(l));
}


static int strL(String s) {
  return s == null ? 0 : s.length();
}


static int listL(Collection l) {
  return l == null ? 0 : l.size();
}


static boolean neq(Object a, Object b) {
  return !eq(a, b);
}


static boolean eqic(String a, String b) {
  
  
    if ((a == null) != (b == null)) return false;
    if (a == null) return true;
    return a.equalsIgnoreCase(b);
  
}


static boolean eqic(Symbol a, Symbol b) {
  return eq(a, b);
}

static boolean eqic(Symbol a, String b) {
  return eqic(asString(a), b);
}


static boolean eqic(char a, char b) {
  if (a == b) return true;
  
    char u1 = Character.toUpperCase(a);
    char u2 = Character.toUpperCase(b);
    if (u1 == u2) return true;
  
  return Character.toLowerCase(u1) == Character.toLowerCase(u2);
}


static boolean ewic(String a, String b) {
  return endsWithIgnoreCase(a, b);
}


static boolean ewic(String a, String b, Matches m) {
  return endsWithIgnoreCase(a, b, m);
}



static Object getOptDynOnly(DynamicObject o, String field) {
  if (o == null || o.fieldValues == null) return null;
  return o.fieldValues.get(field);
}


static <A> Set<A> synchroHashSet() {
  return synchronizedSet(new HashSet<A>());
}





static <A> IF0<A> f0ToIF0(F0<A> f) {
  return f == null ? null : () -> f.get();
}


static <A> HashSet<A> lithashset(A... items) {
  HashSet<A> set = new HashSet();
  for (A a : items) set.add(a);
  return set;
}


static int lCharSequence(CharSequence s) {
  return s == null ? 0 : s.length();
}


static String asString(Object o) {
  return o == null ? null : o.toString();
}


static boolean endsWithIgnoreCase(String a, String b) {
  int la = l(a), lb = l(b);
  return la >= lb && regionMatchesIC(a, la-lb, b, 0, lb);
}


static boolean endsWithIgnoreCase(String a, String b, Matches m) {
  if (!endsWithIgnoreCase(a, b)) return false;
  if (m != null)
    m.m = new String[] { substring(a, 0, l(a)-l(b)) };
  return true;
}





static boolean regionMatchesIC(String a, int offsetA, String b, int offsetB, int len) {
  
  
    return a != null && a.regionMatches(true, offsetA, b, offsetB, len);
  
}




static abstract class VF1<A> implements IVF1<A> {
  public abstract void get(A a);
}
// immutable, has strong refs
// Do not run in a synchronized block - it goes wrong in the presence
// of elaborate classloaders (like in Gazelle BEA)
// see #1102990 and #1102991

final static class _MethodCache {
  final Class c;
  final HashMap<String, List<Method>> cache = new HashMap();
  
  _MethodCache(Class c) {
  this.c = c; _init(); }
  
  void _init() {
    Class _c = c;
    java.lang.Module myModule = getClass().getModule();
    boolean anyHiddenClasses = false;
    
    while (_c != null) {
      boolean exported = classIsExportedTo(_c, myModule);
       
      
      if (!exported)
        anyHiddenClasses = true;
      else
        for (Method m : _c.getDeclaredMethods())
          if ((anyHiddenClasses || !isAbstract(m))
            && !reflection_isForbiddenMethod(m))
            multiMapPut(cache, m.getName(), makeAccessible(m));

      _c = _c.getSuperclass();
    }
    
    // add default methods - this might lead to a duplication
    // because the overridden method is also added, but it's not
    // a problem except for minimal performance loss.
    // If any classes in the hierarchy were inaccessible, we add
    // all interface methods (see test_callForbiddenMethodByReflection for a test)
    
    for (Class intf : allInterfacesImplementedBy(c))
      for (Method m : intf.getDeclaredMethods())
        if ((anyHiddenClasses || m.isDefault()) && !reflection_isForbiddenMethod(m))
          multiMapPut(cache, m.getName(), makeAccessible(m));

     
  }
  
  // Returns only matching methods
  Method findMethod(String method, Object[] args) { try {
    List<Method> m = cache.get(method);
     
    if (m == null) return null;
    int n = m.size();
    for (int i = 0; i < n; i++) {
      Method me = m.get(i);
      if (call_checkArgs(me, args, false))
        return me;
    }
    return null;
  } catch (Exception __e) { throw rethrow(__e); } }
  
  Method findStaticMethod(String method, Object[] args) { try {
    List<Method> m = cache.get(method);
    if (m == null) return null;
    int n = m.size();
    for (int i = 0; i < n; i++) {
      Method me = m.get(i);
      if (isStaticMethod(me) && call_checkArgs(me, args, false))
        return me;
    }
    return null;
  } catch (Exception __e) { throw rethrow(__e); } }
  
  //Cl<Method> allMethods() { ret allValues(cache); }
}
static class Matches {
  String[] m;
  
  Matches() {}
  Matches(String... m) {
  this.m = m;}
  
  String get(int i) { return i < m.length ? m[i] : null; }
  String unq(int i) { return unquote(get(i)); }
  
  String tlc(int i) { return unq(i).toLowerCase(); }
  boolean bool(int i) { return "true".equals(unq(i)); }
  String rest() { return m[m.length-1]; } // for matchStart
  int psi(int i) { return Integer.parseInt(unq(i)); }
  
  public String toString() { return "Matches(" + joinWithComma(quoteAll(asList(m))) + ")"; }
  
  public int hashCode() { return _hashCode(toList(m)); }
  public boolean equals(Object o) { return o instanceof Matches && arraysEqual(m, ((Matches) o).m); }
}

// for the version with MasterSymbol (used WAY back in "Smart Bot"!) see #1010608

static class Symbol implements CharSequence {
  String text;
  
  Symbol() {}
  Symbol(String text, boolean dummy) {
  this.text = text;} // weird signature to prevent accidental calling
  
  public int hashCode() { return _hashCode(text); }
  public String toString() { return text; }
  public boolean equals(Object o) {
    return this == o;
  }

  // implementation of CharSequence methods
  
  public int length() { return text.length(); }
  public char charAt(int index) { return text.charAt(index); }
  public CharSequence subSequence(int start, int end) {
    return text.substring(start, end);
  }
}
static class Var<A> implements IVar<A>, ISetter<A> {
  Var() {}
  Var(A v) {
  this.v = v;}

  
  
  A v; // you can access this directly if you use one thread
  
  public synchronized void set(A a) {
    if (v != a) {
      v = a;
      notifyAll();
    }
  }
  
  public synchronized A get() { return v; }
  public synchronized boolean has() { return v != null; }
  public void clear() { set(null); }

public String toString() { return str(this.get()); }
}
static abstract class F0<A> {
  abstract A get();
}
static abstract class F1<A, B> {
  abstract B get(A a);
}
// you still need to implement hasNext() and next()
static abstract class IterableIterator<A> implements Iterator<A>, Iterable<A> {
  public Iterator<A> iterator() {
    return this;
  }
  
  public void remove() {
    unsupportedOperation();
  }
}
static class MultiMap<A,B> implements IMultiMap<A, B> {
  Map<A, List<B>> data = new HashMap<A, List<B>>();
  int fullSize;
  
  MultiMap() {}
  MultiMap(boolean useTreeMap) { if (useTreeMap) data = new TreeMap(); }
  MultiMap(MultiMap<A, B> map) { putAll(map); }
  MultiMap(Map<A, List<B>> data) {
  this.data = data;}

  void put(A key, B value) { synchronized(data) {
    List<B> list = data.get(key);
    if (list == null)
      data.put(key, list = _makeEmptyList());
    list.add(value);
    ++fullSize;
  }}

  void add(A key, B value) { put(key, value); }

  void addAll(A key, Collection<B> values) { putAll(key, values); }
  
  void addAllIfNotThere(A key, Collection<B> values) { synchronized(data) {
    for (B value : values)
      setPut(key, value);
  }}
  
  void setPut(A key, B value) { synchronized(data) {
    if (!containsPair(key, value))
      put(key, value);
  }}
  
  boolean containsPair(A key, B value) { synchronized(data) {
    return get(key).contains(value);
  }}
  
  void putAll(Collection<A> keys, B value) { synchronized(data) {
    for (A key : unnullForIteration(keys))
      put(key, value);
  }}

  void putAll(A key, Collection<B> values) { synchronized(data) {
    if (nempty(values)) getActual(key).addAll(values);
  }}

  void putAll(Iterable<Pair<A, B>> pairs) { synchronized(data) {
    for (Pair<A, B> p : unnullForIteration(pairs))
      put(p.a, p.b);
  }}
  
  void removeAll(A key, Collection<B> values) { synchronized(data) {
    for (B value : values)
      remove(key, value);
  }}
  
  public List<B> get(A key) { synchronized(data) {
    List<B> list = data.get(key);
    return list == null ? Collections.<B> emptyList() : list;
  }}
  
  List<B> getOpt(A key) { synchronized(data) {
    return data.get(key);
  }}

  List<B> getAndClear(A key) { synchronized(data) {
    List<B> l = cloneList(data.get(key));
    remove(key);
    return l;
  }}
  
  // returns actual mutable live list
  // creates the list if not there
  List<B> getActual(A key) { synchronized(data) {
    List<B> list = data.get(key);
    if (list == null)
      data.put(key, list = _makeEmptyList());
    return list;
  }}
 
  void clean(A key) { synchronized(data) {
    List<B> list = data.get(key);
    if (list != null && list.isEmpty()) {
      fullSize -= l(list);
      data.remove(key);
    }
  }}

  final public Set<A> keys(){ return keySet(); }
public Set<A> keySet() { synchronized(data) {
    return data.keySet();
  }}

  void remove(A key) { synchronized(data) {
    fullSize -= l(this.getOpt(key));
    data.remove(key);
  }}
  
  final void remove(Pair<A, B> p){ removePair(p); }
void removePair(Pair<A, B> p) {
    if (p != null) remove(p.a, p.b);
  }

  void remove(A key, B value) { synchronized(data) {
    List<B> list = data.get(key);
    if (list != null) {
      if (list.remove(value))
        fullSize--;
      if (list.isEmpty())
        data.remove(key);
    }
  }}

  void clear() { synchronized(data) {
    data.clear();
  }}

  boolean containsKey(A key) { synchronized(data) {
    return data.containsKey(key);
  }}

  B getFirst(A key) { synchronized(data) {
    List<B> list = get(key);
    return list.isEmpty() ? null : list.get(0);
  }}
  
  void addAll(MultiMap<A, B> map) { putAll(map); }
  
  void putAll(MultiMap<A, B> map) { synchronized(data) {
    for (A key : map.keySet())
      putAll(key, map.get(key));
  }}
  
  void putAll(Map<A, B> map) { synchronized(data) {
    if (map != null) for (Map.Entry<A, B> e : map.entrySet())
      put(e.getKey(), e.getValue());
  }}
  
  final public int keyCount(){ return keysSize(); }
public int keysSize() { synchronized(data) { return l(data); }}
  
  // full size - note: expensive operation
  final public int fullSize(){ return size(); }
public int size() { synchronized(data) {
    return fullSize;
  }}
  
  // expensive operation
  List<A> reverseGet(B b) { synchronized(data) {
    List<A> l = new ArrayList();
    for (A key : data.keySet())
      if (data.get(key).contains(b))
        l.add(key);
    return l;
  }}
  
  Map<A, List<B>> asMap() { synchronized(data) {
    return cloneMap(data);
  }}
  
  boolean isEmpty() { synchronized(data) { return data.isEmpty(); }}
  
  // override in subclasses
  List<B> _makeEmptyList() {
    return new ArrayList();
  }
  
  // returns live lists
  Collection<List<B>> allLists() {
    synchronized(data) {
      return new ArrayList(data.values());
    }
  }
  Collection<List<B>> values() { return allLists(); }
  
  List<B> allValues() {
    return concatLists(data.values());
  }
  
  Object mutex() { return data; }
  
  public String toString() { return "mm" + str(data); }
}
public static interface IF0<A> {
  A get();
}
static interface Hasher<A> {
  int hashCode(A a);
  boolean equals(A a, A b);
}

static interface IF1<A, B> {
  B get(A a);
}
/*
 * @(#)WeakHashMap.java 1.5 98/09/30
 *
 * Copyright 1998 by Sun Microsystems, Inc.,
 * 901 San Antonio Road, Palo Alto, California, 94303, U.S.A.
 * All rights reserved.
 *
 * This software is the confidential and proprietary information
 * of Sun Microsystems, Inc. ("Confidential Information").  You
 * shall not disclose such Confidential Information and shall use
 * it only in accordance with the terms of the license agreement
 * you entered into with Sun.
 */
 
// From https://github.com/mernst/plume-lib/blob/df0bfafc3c16848d88f4ea0ef3c8bf3367ae085e/java/src/plume/WeakHasherMap.java

static final class WeakHasherMap<K,V> extends AbstractMap<K,V> implements Map<K,V> {

    private Hasher hasher = null;
    /*@Pure*/
    private boolean keyEquals(Object k1, Object k2) {
  return (hasher==null ? k1.equals(k2)
           : hasher.equals(k1, k2));
    }
    /*@Pure*/
    private int keyHashCode(Object k1) {
  return (hasher==null ? k1.hashCode()
           : hasher.hashCode(k1));
    }

    // The WeakKey class can't be static because it depends on the hasher.
    // That in turn means that its methods can't be static.
    // However, I need to be able to call the methods such as create() that
    // were static in the original version of this code.
    // This finesses that.

    private /*@Nullable*/ WeakKey WeakKeyCreate(K k) {
  if (k == null) return null;
  else return new WeakKey(k);
    }
    private /*@Nullable*/ WeakKey WeakKeyCreate(K k, ReferenceQueue<? super K> q) {
  if (k == null) return null;
  else return new WeakKey(k, q);
    }

    // Cannot be a static class: uses keyHashCode() and keyEquals()
    private final class WeakKey extends WeakReference<K> {
  private int hash; /* Hashcode of key, stored here since the key
           may be tossed by the GC */

  private WeakKey(K k) {
      super(k);
      hash = keyHashCode(k);
  }

  private /*@Nullable*/ WeakKey create(K k) {
      if (k == null) return null;
      else return new WeakKey(k);
  }

  private WeakKey(K k, ReferenceQueue<? super K> q) {
      super(k, q);
      hash = keyHashCode(k);
  }

  private /*@Nullable*/ WeakKey create(K k, ReferenceQueue<? super K> q) {
      if (k == null) return null;
      else return new WeakKey(k, q);
  }

        /* A WeakKey is equal to another WeakKey iff they both refer to objects
     that are, in turn, equal according to their own equals methods */
  /*@Pure*/
  @Override
  public boolean equals(/*@Nullable*/ Object o) {
            if (o == null) return false; // never happens
      if (this == o) return true;
            // This test is illegal because WeakKey is a generic type,
            // so use the getClass hack below instead.
      // if (!(o instanceof WeakKey)) return false;
            if (!(o.getClass().equals(WeakKey.class))) return false;
      Object t = this.get();
            @SuppressWarnings("unchecked")
      Object u = ((WeakKey)o).get();
      if ((t == null) || (u == null)) return false;
      if (t == u) return true;
      return keyEquals(t, u);
  }

  /*@Pure*/
  @Override
  public int hashCode() {
      return hash;
  }

    }


    /* Hash table mapping WeakKeys to values */
    private HashMap<WeakKey,V> hash;

    /* Reference queue for cleared WeakKeys */
    private ReferenceQueue<? super K> queue = new ReferenceQueue<K>();


    /* Remove all invalidated entries from the map, that is, remove all entries
       whose keys have been discarded.  This method should be invoked once by
       each public mutator in this class.  We don't invoke this method in
       public accessors because that can lead to surprising
       ConcurrentModificationExceptions. */
    @SuppressWarnings("unchecked")
    private void processQueue() {
  WeakKey wk;
  while ((wk = (WeakKey)queue.poll()) != null) { // unchecked cast
      hash.remove(wk);
  }
    }


    /* -- Constructors -- */

    /**
     * Constructs a new, empty <code>WeakHashMap</code> with the given
     * initial capacity and the given load factor.
     *
     * @param  initialCapacity  the initial capacity of the
     *                          <code>WeakHashMap</code>
     *
     * @param  loadFactor       the load factor of the <code>WeakHashMap</code>
     *
     * @throws IllegalArgumentException  If the initial capacity is less than
     *                                   zero, or if the load factor is
     *                                   nonpositive
     */
    public WeakHasherMap(int initialCapacity, float loadFactor) {
  hash = new HashMap<WeakKey,V>(initialCapacity, loadFactor);
    }

    /**
     * Constructs a new, empty <code>WeakHashMap</code> with the given
     * initial capacity and the default load factor, which is
     * <code>0.75</code>.
     *
     * @param  initialCapacity  the initial capacity of the
     *                          <code>WeakHashMap</code>
     *
     * @throws IllegalArgumentException  If the initial capacity is less than
     *                                   zero
     */
    public WeakHasherMap(int initialCapacity) {
  hash = new HashMap<WeakKey,V>(initialCapacity);
    }

    /**
     * Constructs a new, empty <code>WeakHashMap</code> with the default
     * capacity and the default load factor, which is <code>0.75</code>.
     */
    public WeakHasherMap() {
  hash = new HashMap<WeakKey,V>();
    }

    /**
     * Constructs a new, empty <code>WeakHashMap</code> with the default
     * capacity and the default load factor, which is <code>0.75</code>.
     * The <code>WeakHashMap</code> uses the specified hasher for hashing
     * keys and comparing them for equality.
     * @param h the Hasher to use when hashing values for this map
     */
    public WeakHasherMap(Hasher h) {
  hash = new HashMap<WeakKey,V>();
  hasher = h;
    }


    /* -- Simple queries -- */

    /**
     * Returns the number of key-value mappings in this map.
     * <strong>Note:</strong> <em>In contrast to most implementations of the
     * <code>Map</code> interface, the time required by this operation is
     * linear in the size of the map.</em>
     */
    /*@Pure*/
    @Override
    public int size() {
  return entrySet().size();
    }

    /**
     * Returns <code>true</code> if this map contains no key-value mappings.
     */
    /*@Pure*/
    @Override
    public boolean isEmpty() {
  return entrySet().isEmpty();
    }

    /**
     * Returns <code>true</code> if this map contains a mapping for the
     * specified key.
     *
     * @param   key   the key whose presence in this map is to be tested
     */
    /*@Pure*/
    @Override
    public boolean containsKey(Object key) {
        @SuppressWarnings("unchecked")
        K kkey = (K) key;
  return hash.containsKey(WeakKeyCreate(kkey));
    }


    /* -- Lookup and modification operations -- */

    /**
     * Returns the value to which this map maps the specified <code>key</code>.
     * If this map does not contain a value for this key, then return
     * <code>null</code>.
     *
     * @param  key  the key whose associated value, if any, is to be returned
     */
    /*@Pure*/
    @Override
    public /*@Nullable*/ V get(Object key) {  // type of argument is Object, not K
        @SuppressWarnings("unchecked")
        K kkey = (K) key;
  return hash.get(WeakKeyCreate(kkey));
    }

    /**
     * Updates this map so that the given <code>key</code> maps to the given
     * <code>value</code>.  If the map previously contained a mapping for
     * <code>key</code> then that mapping is replaced and the previous value is
     * returned.
     *
     * @param  key    the key that is to be mapped to the given
     *                <code>value</code>
     * @param  value  the value to which the given <code>key</code> is to be
     *                mapped
     *
     * @return  the previous value to which this key was mapped, or
     *          <code>null</code> if if there was no mapping for the key
     */
    @Override
    public V put(K key, V value) {
  processQueue();
  return hash.put(WeakKeyCreate(key, queue), value);
    }

    /**
     * Removes the mapping for the given <code>key</code> from this map, if
     * present.
     *
     * @param  key  the key whose mapping is to be removed
     *
     * @return  the value to which this key was mapped, or <code>null</code> if
     *          there was no mapping for the key
     */
    @Override
    public V remove(Object key) { // type of argument is Object, not K
  processQueue();
        @SuppressWarnings("unchecked")
        K kkey = (K) key;
  return hash.remove(WeakKeyCreate(kkey));
    }

    /**
     * Removes all mappings from this map.
     */
    @Override
    public void clear() {
  processQueue();
  hash.clear();
    }


    /* -- Views -- */


    /* Internal class for entries */
    // This can't be static, again because of dependence on hasher.
    @SuppressWarnings("TypeParameterShadowing")
    private final class Entry<K,V> implements Map.Entry<K,V> {
  private Map.Entry<WeakKey,V> ent;
  private K key;  /* Strong reference to key, so that the GC
           will leave it alone as long as this Entry
           exists */

  Entry(Map.Entry<WeakKey,V> ent, K key) {
      this.ent = ent;
      this.key = key;
  }

  /*@Pure*/
  @Override
  public K getKey() {
      return key;
  }

  /*@Pure*/
  @Override
  public V getValue() {
      return ent.getValue();
  }

  @Override
  public V setValue(V value) {
      return ent.setValue(value);
  }

        /*@Pure*/
        private boolean keyvalEquals(K o1, K o2) {
      return (o1 == null) ? (o2 == null) : keyEquals(o1, o2);
  }

        /*@Pure*/
        private boolean valEquals(V o1, V o2) {
      return (o1 == null) ? (o2 == null) : o1.equals(o2);
  }

        /*@Pure*/
        @SuppressWarnings("NonOverridingEquals")
        public boolean equals(Map.Entry<K,V> e /* Object o*/) {
            // if (! (o instanceof Map.Entry)) return false;
            // Map.Entry<K,V> e = (Map.Entry<K,V>)o;
      return (keyvalEquals(key, e.getKey())
        && valEquals(getValue(), e.getValue()));
  }

  /*@Pure*/
  @Override
  public int hashCode() {
      V v;
      return (((key == null) ? 0 : keyHashCode(key))
        ^ (((v = getValue()) == null) ? 0 : v.hashCode()));
  }

    }


    /* Internal class for entry sets */
    private final class EntrySet extends AbstractSet<Map.Entry<K,V>> {
  Set<Map.Entry<WeakKey,V>> hashEntrySet = hash.entrySet();

  @Override
  public Iterator<Map.Entry<K,V>> iterator() {

      return new Iterator<Map.Entry<K,V>>() {
    Iterator<Map.Entry<WeakKey,V>> hashIterator = hashEntrySet.iterator();
    Map.Entry<K,V> next = null;

    @Override
    public boolean hasNext() {
        while (hashIterator.hasNext()) {
      Map.Entry<WeakKey,V> ent = hashIterator.next();
      WeakKey wk = ent.getKey();
      K k = null;
      if ((wk != null) && ((k = wk.get()) == null)) {
          /* Weak key has been cleared by GC */
          continue;
      }
      next = new Entry<K,V>(ent, k);
      return true;
        }
        return false;
    }

    @Override
    public Map.Entry<K,V> next() {
        if ((next == null) && !hasNext())
      throw new NoSuchElementException();
        Map.Entry<K,V> e = next;
        next = null;
        return e;
    }

    @Override
    public void remove() {
        hashIterator.remove();
    }

      };
  }

  /*@Pure*/
  @Override
  public boolean isEmpty() {
      return !(iterator().hasNext());
  }

  /*@Pure*/
  @Override
  public int size() {
      int j = 0;
      for (Iterator<Map.Entry<K,V>> i = iterator(); i.hasNext(); i.next()) j++;
      return j;
  }

  @Override
  public boolean remove(Object o) {
      processQueue();
      if (!(o instanceof Map.Entry<?,?>)) return false;
            @SuppressWarnings("unchecked")
      Map.Entry<K,V> e = (Map.Entry<K,V>)o; // unchecked cast
      Object ev = e.getValue();
      WeakKey wk = WeakKeyCreate(e.getKey());
      Object hv = hash.get(wk);
      if ((hv == null)
    ? ((ev == null) && hash.containsKey(wk)) : hv.equals(ev)) {
    hash.remove(wk);
    return true;
      }
      return false;
  }

  /*@Pure*/
  @Override
  public int hashCode() {
      int h = 0;
      for (Iterator<Map.Entry<WeakKey,V>> i = hashEntrySet.iterator(); i.hasNext(); ) {
    Map.Entry<WeakKey,V> ent = i.next();
    WeakKey wk = ent.getKey();
    Object v;
    if (wk == null) continue;
    h += (wk.hashCode()
          ^ (((v = ent.getValue()) == null) ? 0 : v.hashCode()));
      }
      return h;
  }

    }


    private /*@Nullable*/ Set<Map.Entry<K,V>> entrySet = null;

    /**
     * Returns a <code>Set</code> view of the mappings in this map.
     */
    /*@SideEffectFree*/
    @Override
    public Set<Map.Entry<K,V>> entrySet() {
  if (entrySet == null) entrySet = new EntrySet();
  return entrySet;
    }

    // find matching key
    K findKey(Object key) {
      processQueue();
      K kkey = (K) key;
      // TODO: use replacement for HashMap to avoid reflection
      WeakKey wkey = WeakKeyCreate(kkey);
      WeakKey found = hashMap_findKey(hash, wkey);
      return found == null ? null : found.get();
    }
}
static class PersistableThrowable extends DynamicObject {
  String className;
  String msg;
  String stacktrace;
  
  PersistableThrowable() {}
  PersistableThrowable(Throwable e) {
    if (e == null)
      className = "Crazy Null Error";
    else {
      className = getClassName(e).replace('/', '.');
      msg = e.getMessage();
      stacktrace = getStackTrace_noRecord(e);
    }
  }
  
  public String toString() {
    return nempty(msg) ? className + ": " + msg : className;
  }
  
  RuntimeException asRuntimeException() {
    return new Fail(this);
  }
}
static interface IVF1<A> {
  void get(A a);
}
static class Pair<A, B> implements Comparable<Pair<A, B>> {
  A a;
  B b;

  Pair() {}
  Pair(A a, B b) {
  this.b = b;
  this.a = a;}
  
  public int hashCode() {
    return hashCodeFor(a) + 2*hashCodeFor(b);
  }
  
  public boolean equals(Object o) {
    if (o == this) return true;
    if (!(o instanceof Pair)) return false;
    Pair t = (Pair) o;
    return eq(a, t.a) && eq(b, t.b);
  }
  
  public String toString() {
    return "<" + a + ", " + b + ">";
  }
  
  public int compareTo(Pair<A, B> p) {
    if (p == null) return 1;
    int i = ((Comparable<A>) a).compareTo(p.a);
    if (i != 0) return i;
    return ((Comparable<B>) b).compareTo(p.b);
  }
}


static interface ISetter<A> {
 void set(A a);
}

interface IMultiMap<A, B> {
  public Set<A> keySet();
  public Collection<B> get(A a);
  public int size();
  public int keyCount();
}
static interface IVar<A> extends IF0<A> {
  void set(A a);
  A get();
  
  // reified type of value (if available)
  default Class<A> getType() { return null; }
  
  
  default boolean has() { return get() != null; }
  default void clear() { set(null); }
  
}


static Class<?> getClass(String name) {
  return _getClass(name);
}

static Class getClass(Object o) {
  return _getClass(o);
}

static Class getClass(Object realm, String name) {
  return _getClass(realm, name);
}


static boolean classIsExportedTo(Class c, java.lang.Module destModule) {
  if (c == null || destModule == null) return false;
  
  java.lang.Module srcModule = c.getModule();
  String packageName = c.getPackageName();
  return srcModule.isExported(packageName, destModule);
}


static boolean isAbstract(Class c) {
  return (c.getModifiers() & Modifier.ABSTRACT) != 0;
}

static boolean isAbstract(Method m) {
  return (m.getModifiers() & Modifier.ABSTRACT) != 0;
}


static boolean reflection_isForbiddenMethod(Method m) {
  return m.getDeclaringClass() == Object.class
    && eqOneOf(m.getName(), "finalize", "clone", "registerNatives");
}


static Set<Class> allInterfacesImplementedBy(Class c) {
  if (c == null) return null;
  HashSet<Class> set = new HashSet();
  allInterfacesImplementedBy_find(c, set);
  return set;
}

static void allInterfacesImplementedBy_find(Class c, Set<Class> set) {
  if (c.isInterface() && !set.add(c)) return;
  do {
    for (Class intf : c.getInterfaces())
      allInterfacesImplementedBy_find(intf, set);
  } while ((c = c.getSuperclass()) != null);
}


static Method findMethod(Object o, String method, Object... args) {
  return findMethod_cached(o, method, args);
}

static boolean findMethod_checkArgs(Method m, Object[] args, boolean debug) {
  Class<?>[] types = m.getParameterTypes();
  if (types.length != args.length) {
    if (debug)
      System.out.println("Bad parameter length: " + args.length + " vs " + types.length);
    return false;
  }
  for (int i = 0; i < types.length; i++)
    if (!(args[i] == null || isInstanceX(types[i], args[i]))) {
      if (debug)
        System.out.println("Bad parameter " + i + ": " + args[i] + " vs " + types[i]);
      return false;
    }
  return true;
}


static Method findStaticMethod(Class c, String method, Object... args) {
  Class _c = c;
  while (c != null) {
    for (Method m : c.getDeclaredMethods()) {
      if (!m.getName().equals(method))
        continue;

      if ((m.getModifiers() & Modifier.STATIC) == 0 || !findStaticMethod_checkArgs(m, args))
        continue;

      return m;
    }
    c = c.getSuperclass();
  }
  return null;
}

static boolean findStaticMethod_checkArgs(Method m, Object[] args) {
  Class<?>[] types = m.getParameterTypes();
  if (types.length != args.length)
    return false;
  for (int i = 0; i < types.length; i++)
    if (!(args[i] == null || isInstanceX(types[i], args[i])))
      return false;
  return true;
}



static String unquote(String s) {
  if (s == null) return null;
  if (startsWith(s, '[')) {
    int i = 1;
    while (i < s.length() && s.charAt(i) == '=') ++i;
    if (i < s.length() && s.charAt(i) == '[') {
      String m = s.substring(1, i);
      if (s.endsWith("]" + m + "]"))
        return s.substring(i+1, s.length()-i-1);
    }
  }
  
  if (s.length() > 1) {
    char c = s.charAt(0);
    if (c == '\"' || c == '\'') {
      int l = endsWith(s, c) ? s.length()-1 : s.length();
      StringBuilder sb = new StringBuilder(l-1);
  
      for (int i = 1; i < l; i++) {
        char ch = s.charAt(i);
        if (ch == '\\') {
          char nextChar = (i == l - 1) ? '\\' : s.charAt(i + 1);
          // Octal escape?
          if (nextChar >= '0' && nextChar <= '7') {
              String code = "" + nextChar;
              i++;
              if ((i < l - 1) && s.charAt(i + 1) >= '0'
                      && s.charAt(i + 1) <= '7') {
                  code += s.charAt(i + 1);
                  i++;
                  if ((i < l - 1) && s.charAt(i + 1) >= '0'
                          && s.charAt(i + 1) <= '7') {
                      code += s.charAt(i + 1);
                      i++;
                  }
              }
              sb.append((char) Integer.parseInt(code, 8));
              continue;
          }
          switch (nextChar) {
          case '\"': ch = '\"'; break;
          case '\\': ch = '\\'; break;
          case 'b': ch = '\b'; break;
          case 'f': ch = '\f'; break;
          case 'n': ch = '\n'; break;
          case 'r': ch = '\r'; break;
          case 't': ch = '\t'; break;
          case '\'': ch = '\''; break;
          // Hex Unicode: u????
          case 'u':
              if (i >= l - 5) {
                  ch = 'u';
                  break;
              }
              int code = Integer.parseInt(
                      "" + s.charAt(i + 2) + s.charAt(i + 3)
                         + s.charAt(i + 4) + s.charAt(i + 5), 16);
              sb.append(Character.toChars(code));
              i += 5;
              continue;
          default:
            ch = nextChar; // added by Stefan
          }
          i++;
        }
        sb.append(ch);
      }
      return sb.toString();
    }
  }
    
  return s; // not quoted - return original
}


static List<String> quoteAll(String[] l) {
  return quoteAll(asList(l));
}

static List<String> quoteAll(Collection<String> l) {
  List<String> x = new ArrayList();
  for (String s : l)
    x.add(quote(s));
  return x;
}


static <A> ArrayList<A> toList(A[] a) { return asList(a); }
static ArrayList<Integer> toList(int[] a) { return asList(a); }
static <A> ArrayList<A> toList(Set<A> s) { return asList(s); }
static <A> ArrayList<A> toList(Iterable<A> s) { return asList(s); }


static boolean arraysEqual(Object[] a, Object[] b) {
  if (a.length != b.length) return false;
  for (int i = 0; i < a.length; i++)
    if (neq(a[i], b[i])) return false;
  return true;
}


static <A> Iterator<A> iterator(Iterable<A> c) {
  return c == null ? emptyIterator() : c.iterator();
}


static UnsupportedOperationException unsupportedOperation() {
  throw new UnsupportedOperationException();
}


static <A, B> Map<A, B> putAll(Map<A, B> a, Map<? extends A,? extends B> b) {
  if (a != null && b != null) a.putAll(b);
  return a;
}


static <A, B> MultiMap<A, B> putAll(MultiMap<A, B> a, Map<? extends A,? extends B> b) {
  if (a != null) a.putAll((Map) b);
  return a;
}


static <A, B> Map<A, B> putAll(Map<A, B> a, Object... b) {
  if (a != null)
    litmap_impl(a, b);
  return a;
}



static <A> void remove(List<A> l, int i) {
  if (l != null && i >= 0 && i < l(l))
    l.remove(i);
}

static <A> void remove(Collection<A> l, A a) {
  if (l != null) l.remove(a);
}

static <A, B> B remove(Map<A, B> map, Object a) {
  return map == null ? null : map.remove(a);
}

static void remove(BitSet bs, int i) {
  bs.clear(i);
}


static <A> A getAndClear(IVar<A> v) {
  A a = v.get();
  v.set(null);
  return a;
}


static <A, B> Set<A> keys(Map<A, B> map) {
  return map == null ? new HashSet() : map.keySet();
}

// convenience shortcut for keys_gen
static Set keys(Object map) {
  return keys((Map) map);
}




  static <A, B> Set<A> keys(IMultiMap<A, B> mm) {
    return mm.keySet();
  }





static <A, B> Set<A> keySet(Map<A, B> map) {
  return map == null ? new HashSet() : map.keySet();
}

static Set keySet(Object map) {
  return keys((Map) map);
}




  static <A, B> Set<A> keySet(MultiMap<A, B> mm) {
    return mm.keySet();
  }





static <A, B> int keysSize(MultiMap<A, B> mm) {
  return lKeys(mm);
}


static <A> A reverseGet(List<A> l, int idx) {
  if (l == null || idx < 0) return null;
  int n = l(l);
  return idx < n ? l.get(n-1-idx) : null;
}


static <A, B> Map<A, B> cloneMap(Map<A, B> map) {
  if (map == null) return new HashMap();
  // assume mutex is equal to map
  synchronized(map) {
    return map instanceof TreeMap ? new TreeMap((TreeMap) map) // copies comparator
      : map instanceof LinkedHashMap ? new LinkedHashMap(map)
      : new HashMap(map);
  }
}

static <A, B> List<B> cloneMap(Iterable<A> l, IF1<A, B> f) {
  List x = emptyList(l);
  if (l != null) for (A o : cloneList(l))
    x.add(f.get(o));
  return x;
}


static <A, B> Collection<B> values(Map<A, B> map) {
  return map == null ? emptyList() : map.values();
}

// convenience shortcut for values_gen
static Collection values(Object map) {
  return values((Map) map);
}


static <A, B> Collection<B> values(MultiMap<A, B> mm) {
  return mm == null ? emptyList() : concatLists(values(mm.data));
}





static <A, B, C extends Collection<B>> List<B> allValues(Map<A, C> map) {
  List<B> out = new ArrayList();
  for (var l : values(map))
    addAll(out, l);
  return out;
}


static <A> List<A> concatLists(Iterable<A>... lists) {
  List<A> l = new ArrayList();
  if (lists != null) for (Iterable<A> list : lists)
    addAll(l, list);
  return l;
}

static <A> List<A> concatLists(Collection<? extends Iterable<A>> lists) {
  List<A> l = new ArrayList();
  if (lists != null) for (Iterable<A> list : lists)
    addAll(l, list);
  return l;
}



static Method hashMap_findKey_method;

static <A, B> A hashMap_findKey(HashMap<A, B> map, Object key) { try {
  if (hashMap_findKey_method == null)
    hashMap_findKey_method = findMethodNamed(HashMap.class, "getNode");
  Map.Entry<A, B> entry = (Map.Entry) hashMap_findKey_method.invoke(map, hashMap_internalHash(key), key);
  // java.util.Map.Entry<A, B> entry = (java.util.Map.Entry) call(hash, 'getNode, hashMap_internalHash(key), wkey);
  return entry == null ? null : entry.getKey();
} catch (Exception __e) { throw rethrow(__e); } }


static int hashCodeFor(Object a) {
  return a == null ? 0 : a.hashCode();
}


static <A> A set(A o, String field, Object value) {
  if (o == null) return null;
  if (o instanceof Class) set((Class) o, field, value);
  else try {
    Field f = set_findField(o.getClass(), field);
    makeAccessible(f);
    smartSet(f, o, value);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
  return o;
}

static void set(Class c, String field, Object value) {
  if (c == null) return;
  try {
    Field f = set_findStaticField(c, field);
    makeAccessible(f);
    smartSet(f, null, value);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
}
  
static Field set_findStaticField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field) && (f.getModifiers() & java.lang.reflect.Modifier.STATIC) != 0)
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  throw new RuntimeException("Static field '" + field + "' not found in " + c.getName());
}

static Field set_findField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field))
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  throw new RuntimeException("Field '" + field + "' not found in " + c.getName());
}

static void set(BitSet bs, int idx) {
  { if (bs != null) bs.set(idx); }
}




static boolean eqOneOf(Object o, Object... l) {
  for (Object x : l) if (eq(o, x)) return true; return false;
}


static Method findMethod_cached(Object o, String method, Object... args) { try {
  if (o == null) return null;
  if (o instanceof Class) {
    _MethodCache cache = callOpt_getCache((Class) o);
    List<Method> methods = cache.cache.get(method);
    if (methods != null) for (Method m : methods)
      if (isStaticMethod(m) && findMethod_checkArgs(m, args, false))
        return m;
    return null;
  } else {
    _MethodCache cache = callOpt_getCache(o.getClass());
    List<Method> methods = cache.cache.get(method);
    if (methods != null) for (Method m : methods)
      if (findMethod_checkArgs(m, args, false))
        return m;
    return null;
  }
} catch (Exception __e) { throw rethrow(__e); } }



static boolean endsWith(String a, String b) {
  return a != null && a.endsWith(b);
}

static boolean endsWith(String a, char c) {
  return nempty(a) && lastChar(a) == c;
}


  static boolean endsWith(String a, String b, Matches m) {
    if (!endsWith(a, b)) return false;
    m.m = new String[] {dropLast(l(b), a)};
    return true;
  }




static String quote(Object o) {
  if (o == null) return "null";
  return quote(str(o));
}

static String quote(String s) {
  if (s == null) return "null";
  StringBuilder out = new StringBuilder((int) (l(s)*1.5+2));
  quote_impl(s, out);
  return out.toString();
}
  
static void quote_impl(String s, StringBuilder out) {
  out.append('"');
  int l = s.length();
  for (int i = 0; i < l; i++) {
    char c = s.charAt(i);
    if (c == '\\' || c == '"')
      out.append('\\').append(c);
    else if (c == '\r')
      out.append("\\r");
    else if (c == '\n')
      out.append("\\n");
    else if (c == '\t')
      out.append("\\t");
    else if (c == '\0')
      out.append("\\0");
    else
      out.append(c);
  }
  out.append('"');
}


static Iterator emptyIterator() {
  return Collections.emptyIterator();
}


static HashMap litmap(Object... x) {
  HashMap map = new HashMap();
  litmap_impl(map, x);
  return map;
}

static void litmap_impl(Map map, Object... x) {
  if (x != null) for (int i = 0; i < x.length-1; i += 2)
    if (x[i+1] != null)
      map.put(x[i], x[i+1]);
}


static <A, B> int lKeys(MultiMap<A, B> mm) {
  return mm == null ? 0 : mm.keysSize();
}


static <A, B extends A> void addAll(Collection<A> c, Iterable<B> b) {
  if (c != null && b != null) for (A a : b) c.add(a);
}

static <A, B extends A> boolean addAll(Collection<A> c, Collection<B> b) {
  return c != null && b != null && c.addAll(b);
}

static <A, B extends A> boolean addAll(Collection<A> c, B... b) {
  return c != null && b != null && c.addAll(Arrays.asList(b));
}



static <A, B> Map<A, B> addAll(Map<A, B> a, Map<? extends A,? extends B> b) {
  if (a != null && b != null) a.putAll(b);
  return a;
}

static <A extends Container> A addAll(A c, Collection<? extends Component> components) {
  return addComponents(c, components);
}

static <A extends Container> A addAll(A c, Component... components) {
  return addComponents(c, components);
}


// This is a bit rough... finds static and non-static methods.

static Method findMethodNamed(Object obj, String method) {
  if (obj == null) return null;
  if (obj instanceof Class)
    return findMethodNamed((Class) obj, method);
  return findMethodNamed(obj.getClass(), method);
}

static Method findMethodNamed(Class c, String method) {
  while (c != null) {
    for (Method m : c.getDeclaredMethods())
      if (m.getName().equals(method)) {
        makeAccessible(m);
        return m;
      }
    c = c.getSuperclass();
  }
  return null;
}


static int hashMap_internalHash(Object key) {
  int h;
  return (key == null) ? 0 : (h = key.hashCode()) ^ (h >>> 16);
}


static void smartSet(Field f, Object o, Object value) throws Exception {
  try {
    f.set(o, value);
  } catch (Exception e) {
    Class type = f.getType();
    
    // take care of common case (long to int)
    if (type == int.class && value instanceof Long)
      { f.set(o, ((Long) value).intValue()); return; }
      
    if (type == boolean.class && value instanceof String)
      { f.set(o, isTrueOrYes(((String) value))); return; }
    
    if (type == LinkedHashMap.class && value instanceof Map)
      { f.set(o, asLinkedHashMap((Map) value)); return; }
    
    
    throw e;
  }
}




static char lastChar(String s) {
  return empty(s) ? '\0' : s.charAt(l(s)-1);
}


static <A> A[] dropLast(A[] a) { return dropLast(a, 1); }
static <A> A[] dropLast(A[] a, int n) {
  if (a == null) return null;
  n = Math.min(n, a.length);
  A[] b = arrayOfSameType(a, a.length-n);
  System.arraycopy(a, 0, b, 0, b.length);
  return b;
}

static <A> List<A> dropLast(List<A> l) {
  return subList(l, 0, l(l)-1);
}

static <A> List<A> dropLast(int n, List<A> l) {
  return subList(l, 0, l(l)-n);
}

static <A> List<A> dropLast(Iterable<A> l) {
  return dropLast(asList(l));
}

static String dropLast(String s) {
  return substring(s, 0, l(s)-1);
}

static String dropLast(String s, int n) {
  return substring(s, 0, l(s)-n);
}

static String dropLast(int n, String s) {
  return dropLast(s, n);
}



static <A extends Container> A addComponents(A c, Collection<? extends Component> components) {
  if (nempty(components)) { swing(() -> { 
    for (Component comp : components)
      if (comp != null)
        c.add(comp);
    revalidate(c);
  }); }
  return c;
}

static <A extends Container> A addComponents(A c, Component... components) {
  return addComponents(c, asList(components));
}


static boolean isTrueOrYes(Object o) {
  return isTrueOpt(o) || o instanceof String && (eqicOneOf(((String) o), "1", "t", "true") || isYes(((String) o)));
}


static <A, B> LinkedHashMap<A, B> asLinkedHashMap(Map<A, B> map) {
  if (map instanceof LinkedHashMap) return (LinkedHashMap) map;
  LinkedHashMap<A, B> m = new LinkedHashMap();
  if (map != null) synchronized(collectionMutex(map)) {
    m.putAll(map);
  }
  return m;
}




static <A> A[] arrayOfSameType(A[] a, int n) {
  return newObjectArrayOfSameType(a, n);
}


static <A> List<A> subList(List<A> l, int startIndex) {
  return subList(l, startIndex, l(l));
}

static <A> List<A> subList(int startIndex, List<A> l) {
  return subList(l, startIndex);
}

static <A> List<A> subList(int startIndex, int endIndex, List<A> l) {
  return subList(l, startIndex, endIndex);
}

static <A> List<A> subList(List<A> l, int startIndex, int endIndex) {
  if (l == null) return null;
  int n = l(l);
  startIndex = Math.max(0, startIndex);
  endIndex = Math.min(n, endIndex);
  if (startIndex > endIndex) return ll();
  if (startIndex == 0 && endIndex == n) return l;
  
  
    return l.subList(startIndex, endIndex);
  
}




static <A extends Component> A revalidate(final A c) {
  if (c == null || !c.isShowing()) return c;
  { swing(() -> { 
    // magic combo to actually relayout and repaint
    c.revalidate();
    c.repaint();
  }); }
  return c;
}

static void revalidate(JFrame f) { revalidate((Component) f); }
static void revalidate(JInternalFrame f) { revalidate((Component) f); }


static boolean isTrueOpt(Object o) {
  if (o instanceof Boolean)
    return ((Boolean) o).booleanValue();
  return false;
}

static boolean isTrueOpt(String field, Object o) {
  return isTrueOpt(getOpt(field, o));
}


static boolean eqicOneOf(String s, String... l) {
  for (String x : l) if (eqic(s, x)) return true; return false;
}


static List<String> isYes_yesses = litlist("y", "yes", "yeah", "y", "yup", "yo", "corect", "sure", "ok", "afirmative"); // << collapsed words, so "corect" means "correct"

static boolean isYes(String s) {
  return isYes_yesses.contains(collapseWord(toLowerCase(firstWord2(s))));
}




static <A> A[] newObjectArrayOfSameType(A[] a) { return newObjectArrayOfSameType(a, a.length); }
static <A> A[] newObjectArrayOfSameType(A[] a, int n) {
  return (A[]) Array.newInstance(a.getClass().getComponentType(), n);
}


static <A> ArrayList<A> litlist(A... a) {
  ArrayList l = new ArrayList(a.length);
  for (A x : a) l.add(x);
  return l;
}


static String collapseWord(String s) {
  if (s == null) return "";
  StringBuilder buf = new StringBuilder();
  for (int i = 0; i < l(s); i++)
    if (i == 0 || !charactersEqualIC(s.charAt(i), s.charAt(i-1)))
      buf.append(s.charAt(i));
  return buf.toString();
}


static List<String> toLowerCase(List<String> strings) {
  List<String> x = new ArrayList();
  for (String s : strings)
    x.add(s.toLowerCase());
  return x;
}

static String[] toLowerCase(String[] strings) {
  String[] x = new String[l(strings)];
  for (int i = 0; i < l(strings); i++)
    x[i] = strings[i].toLowerCase();
  return x;
}

static String toLowerCase(String s) {
  return s == null ? "" : s.toLowerCase();
}


static String firstWord2(String s) {
  s = xltrim(s);
  if (empty(s)) return "";
  if (isLetterOrDigit(first(s)))
    return takeCharsWhile(__37 -> isLetterOrDigit(__37), s);
  else return "" + first(s);
}




static boolean charactersEqualIC(char c1, char c2) {
  if (c1 == c2) return true;
  char u1 = Character.toUpperCase(c1);
  char u2 = Character.toUpperCase(c2);
  if (u1 == u2) return true;
  return Character.toLowerCase(u1) == Character.toLowerCase(u2);
}



static String xltrim(String s) {
  int i = 0, n = l(s);
  while (i < n && contains(" \t\r\n", s.charAt(i)))
    ++i;
  return substr(s, i);
}


static boolean isLetterOrDigit(char c) {
  return Character.isLetterOrDigit(c);
}


// pred: char -> bool
static String takeCharsWhile(String s, Object pred) {
  int i = 0;
  while (i < l(s) && isTrue(callF(pred, s.charAt(i)))) ++i;
  return substring(s, 0, i);
}

static String takeCharsWhile(IF1<Character, Boolean> f, String s) {
  return takeCharsWhile(s, f);
}




static String substr(String s, int x) {
  return substring(s, x);
}

static String substr(String s, int x, int y) {
  return substring(s, x, y);
}



}