run-time-compiled regexes

[Sam Bishop]

I'm trying to write my first flex-generated scanner and have gotten a
little stuck.

I'm trying to scan simulation output files.  These files declare in their
preambles what separator is used throughout the rest of the file.  Is
there any way to plug the separator into the regular expressions used for
scanning the rest of the file, on the fly?  I think that the separator is
always a single character, but a string solution would also be
appreciated.

Thanks in advance,
Sam