[antlr-interest] newbie question, escaped characters

[Rob Shields]

Richard Clark wrote:
> When you added:
> 
>   protected WILDCARD_TERM_CHAR: '\\' ( '*' | '?' );
> 
> did you remove the * and ? from ESCAPED_TERM_CHAR?
> 
> ...Richard

Yes I did. So the whole thing looks like this:

protected TERM_CHAR: SIMPLE_TERM_CHAR | ESCAPED_TERM_CHAR | 
WILDCARD_TERM_CHAR;

protected SIMPLE_TERM_CHAR:  ~( ' ' | '\t' | '!' | '(' | ')' | ':' | '^' |
                          '[' | ']' | '\\' | '\"' | '{' | '}' | '~' | '/' |
                          '\r' | '\n' );

protected ESCAPED_TERM_CHAR:  '\\'! ( '\\' | '+'  | '-' | '!' | '(' | 
')' | ':' | '^' |
                               '[' | ']' | '\"' | '{' | '}' | '~' | '/');

protected WILDCARD_TERM_CHAR: '\\' ( '*' | '?' );

This gives a warning about lexical nondeterminism (ESCAPED_TERM_CHAR and 
WILDCARD_TERM_CHAR both start with \) and WILDCARD_TERM_CHAR doesn't 
work. If I swap around ESCAPED_TERM_CHAR and WILDCARD_TERM_CHAR, then 
ESCAPED_TERM_CHAR doesn't work.

Rob