[antlr-interest] How do you use template output with backtracking on in a validating semantic predicate?

[Terence Parr]

You can also use a predicate in front of the template

-> {...}? template
-> {...}? template2
-> template3

Ter
On Jul 2, 2007, at 10:54 AM, Richard Clark wrote:

> OK, I see what you're doing: selecting a different output template
> based on type info in your symbol table. The trick is to change the
> piece that creates your template. Try this:
>
> ^('==' left=expression right=expression) ->
> { String template = (isString($left.st} && isString($right.st)) ?
> "stringEqual" : "equal";
> templateLib.getInstanceOf(template,
>               new STAttrMap().put("left", left.st).put("right",  
> right.st);
> }
>
> The secret is the "-> {...}" bit. It says "I'll construct the string
> template myself, thank you."
>
> ...Richard