docs: protected boolean dequeued() throws CompilationFailedException {
          boolean dequeue = !queuedSources.isEmpty();
          while (!queuedSources.isEmpty()) {
              SourceUnit su = queuedSources.removeFirst();
              String name = su.getName();
              names.add(name);
              sources.put(name, su);
          }
          if (dequeue) {
              gotoPhase(Phases.INITIALIZATION);
          }
          return dequeue;
      }