c,regex,compiler-construction,lex , How i can disable maximal munch rule in Lex?

How i can disable maximal munch rule in Lex?


Tag: c,regex,compiler-construction,lex

Suppose i want to deal with certain patterns and have the other text(VHDL code) as it is in the output file.

For that purpose i would be required to write a master rule in the end as

// do something with my pattern



Problem with this strategy is MY_PATTERN is useless in this case and would be matched with .* by maximum munch rule.

So how can i get this functionality ?


The easy way is to get rid of the * in your default rule at the end and just use

.    { append_to_buffer(*yytext); }

so your default rule takes all the stuff that isn't matched by the previous rules and stuffs it off in a buffer somehwere to be dealt with by someone else.


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