!7

static O host;
static SimpleLiveValue<S> lv = new(S);
static SimpleLiveValue<S> input = new(S);
static ReliableSingleThread rst = new(f parse);

static JComponent visualize() { ret jLiveValueTextArea(lv); }

p { input.onChange(rTrigger(rst)); }
svoid update { input.set((S) callOpt(creator(), 'getInterestingString)); }

svoid parse {
  S text;
  lv.set("Parsing...");
  try {
    javaParseCompilationUnit(last);
    text = "Text parses as Java compilation unit";
  } catch e {
    text = firstLine(getInnerMessage(e));
  }
  lv.set(text);
}