I was just asked if I knew of any regular expression library which could be called from Fortran ...

I've just had a look through both first and second editions of the "Regular Expression book"   http://www.wellho.net/book/0-596-00289-0.html and neither even mentions Fortran.   My own tendency (from a Unix / Linux background) would be to call re_comp and re_exec in C.   C can be called from Fortran on any Unix or Linux box from probably any compiler ....

Are you looking for a Windows solution? I've certainly run C from Fortran using Microsoft's compilers, so i suspect you could pick up a C regular expression handler and compile it up - but I'm not sure about a DLL distribution.   You could also embed Tcl.

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