Mark-Jason Dominus wrote a regex-to-text-stream program in ML, and I wrote one in Perl. The process is not terribly difficult, but it can become difficult if allow things like look-ahead and look-behind and deferred-evaluation assertions.

Basically, you must parse a regex into its parts. Then work along these parts, one by one, building a string. 

/^\w+\s+(\d{3}|\w+)/

\w+ => "j30_98a3"
\s+ => "\n\n\t   \r"
\d{3} => "523"

(or)

\w+ => "j30_98a3"
\s+ => "\n\n\t   \r"
\w+ => "r4_QK4"

[download]
You basically produce a string by processing the NODE and its QUANTIFIER. I might produce a module to do this in the upcoming rewrite of my regex parser, to appear in the Regexp::Parser hierarchy. Or perhaps Regex::Parser. I don't know.

_____________________________________________________
Jeff[japhy]Pinyan: Perl, regex, and perl hacker.
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;

In reply to Re: expanding regexps, question with no answer yet by japhy
in thread expanding regexps, question with no answer yet by Anonymous Monk

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