[antlr-interest] Debugging tree parser antlr 2.7.5

[Xue Yong Zhi]

> 
> <AST>:0:0: unexpected end of subtree
> 
> How do I debug this? I have added    genHashLines = true;      to both 
> the regular parser as well as the tree parser, however I still get 
> <AST>:0:0
> How can I pinpoint the exact location where the problem is?

The default AST node does not store line information. You can try to 
replace it with the follwoing:
http://xruby.googlecode.com/svn/trunk/src/com/xruby/compiler/parser/ASTWithLineNumber.java

Then in your parser, call this:
setASTNodeClass("com.xruby.compiler.parser.ASTWithLineNumber");

Btw, println is helpful for debugging, as always:)
AST ast = parser.getAST();
System.out.println(ast.toStringList());