The Debugger

ANTLRWorks is able to debug any grammar using a simple language agnostic protocol even if the target language is not Java.

The various elements are:

• Control buttons: buttons used to control the debugger (e.g. stop, play forward, backward). Move the mouse over a button to have a small tooltip displayed. Note that some of these buttons allow to go back in the stream of events: this is particularly useful when you want to replay a portion of events without having to stop and relaunch the debugger (note that the actions are executed only once, during the first pass).
• Break buttons: use these buttons to tell the debugger at which event it should break.
  • All: break on all events
  • Location: breaks on Location events (when the parser moves in the grammar)
  • Consume: breaks on Consume events (when the parser is consuming a token)
  • LT: breaks on LT events (when the parser is looking ahead)
  • Exception: breaks on Exceptions events
• Status: status of the debugger.
• Detachable panels: there are six panels that can be detached from the main window using the Detach button. These panels are:
  • Input: shows the input tokens being consumed.
  • Output: shows the output from the parser being debugged.
  • Parse Tree: shows the parse tree
  • AST: shows the abstract syntax tree (if generated by the grammar)
  • Stack: shows the current stack of rules
  • Events: shows the list of events that have been sent by the parser to the debugger

Remote Debugger