!7

static SimpleLiveValue<S> output = new(S);
static SimpleLiveValue<S> input = new(S);
static ReliableSingleThread rst = new(f parse);

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

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

svoid parse {
  output.set("Parsing...");
  try {
    javaParseCompilationUnit(input!);
    output.set("Text parses as Java compilation unit");
  } catch e {
    output.set(firstLine(getInnerMessage(e)));
  }
}