c - Regular expression for a string literal in flex/lex

Question

I'm experimenting to learn flex and would like to match string literals. My code currently looks like:

"""([^
"\]*(\[.
])*)*"""        {/*matches string-literal*/;}

I've been struggling with variations for an hour or so and can't get it working the way it should. I'm essentially hoping to match a string literal that can't contain a new-line (unless it's escaped) and supports escaped characters.

I am probably just writing a poor regular expression or one incompatible with flex. Please advise!

Answer 1

A string consists of a quote mark

"

followed by zero or more of either an escaped anything

\.

or a non-quote character, non-backslash character

[^"\]

and finally a terminating quote

"

Put it all together, and you've got

"(\.|[^"\])*"

The delimiting quotes are escaped because they are Flex meta-characters.