[antlr-interest] "An Introduction to ANTLR" presentation slides

[Andy Tripp]

Terence Parr wrote:
>
> A syn pred simply specifies the sytnactic context that must be true 
> for the parser (or lexer or tree parser) to pass.  
Ah, OK. So my slide is wrong.

I guess I tend to wrongly equate "syntax" with a lexer and "semantics" 
with a parser.

So a syntactic predicate can apply to lexer, parser, or treewalker.
And I guess a syntactic predicate is a specific kind of semantic 
predicate. Whereas a sem pred is
any boolean expression that must be true to match, a syn pred is one 
that simply says
"look ahead and see if we'll match X".