[antlr-interest] more Tree visitor thoughts

[Terence Parr]

Hi. I have a decent prototype implementation of an automatic tree construction mechanism for ANTLR 4 working, which I describe here:

http://bit.ly/nh8RmL

My basic goal here is to allow newbies and experts alike to get something running quickly by simply implementing a listener interface automatically generated by ANTLR. The grammar would not need any actions at all and there would be no special flag on the command line to generate parsers capable of building these automatic trees--it's a simple Boolean flag set in the parser, indicating if these trees should be built.

Please let me know if you think this would be useful.

Ter