[antlr-interest] Languages where keywords can be used as identifiers

[Thomas Krebs]

John Green wrote:
>> Are there any hooks (from the parser) into the lexer, to tell it to
>> switch off testLiterals, or (due to lookahead) is it already too late
>> once the parser is parsing a rule?
> 
> 
> Due to the lookahead, it's already too late. Having the parser trigger 
> state switches in the lexer just leads to a world of hurt.
> 
> I agree about the maintenance issue with regard to keeping a list of 
> unreserved keywords. The grammar I maintain (I wrote a parser for a 
> language called ABL from Progress Software) has over 1000 token types 
> now, most of those are unreserved keywords. I had hoped that your 
> situation was different.
> 
> I don't know of any way around the fact that all of the unreserved 
> keywords need to be listed as a rule in your grammar. The parser that 
> Antlr generates needs that rule so that it can deal with lookahead issues.
> 
> John at joanju dot com
> 

Facing the same problem at the same time (see my post: "literal and
string distinction", I got an idea:
Wouldn't it make sense (if possible?) to switch between different lexers
with one dealing with keywords and the other not?
Is switching of lexers possible/supported or does lookahead render this
impossible?

Thomas