[antlr-interest] Composite Grammar problem/CoomonToken suggestion
Gavin Lambert
antlr at mirality.co.nz
Fri May 16 00:39:28 PDT 2008
At 10:42 16/05/2008, Johannes Luber wrote:
>Thinking about the "first comes first"-rule precendence in
>inheriting the grammars, I came up with a case that doesn't seem
to
>be supported. If grammar A defines the rules r and s, as does
>grammar B, then the rules in B are ignored. What if you want
only
>the rule s in B instead of s in A taking precedence? Switching
the
>grammars around doesn't help.
Bear in mind that I haven't so much as even glanced at the grammar
inheritance stuff yet, but assuming it operates similar to general
inheritance -- can you factor out one of the rules to a common
base grammar? That ought to sort it out.
>Also did you see my suggestion regarding CommonToken? If you add
a
>string field then "!" can be made work in the lexer without
>sacrificing speed for the normal cases. It just requires an
>overhead for the pointer.
I would love for ! to work in the lexer again. Although for my
purposes it's not especially useful unless it also works in
fragment rules, which is a bit of a trickier task (with the
current design).
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