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The good thing about Perl regex is that you don't have to write the entire regex in one go, you can build it part by part programmatically. I often construct my regex in the maner as shown below to improve readability (at least to myself) and maintainability:
use strict; use warnings; # allowed prompt characters my $prompt_regex = '[>$%@~# ]'; # allowed characters in the prompt my $allowed_regex = '[\w@\-\.]*'; # a list of allowed prompt patterns my @patterns = ( '\[?' . $allowed_regex . $prompt_regex . '\]?', quotemeta '\\[\\e[0m\\] [0m', ); # build my regex dynamically my $regex = '(' . join('|',@patterns) .')\s?'; # test the regex print "regex: /$regex/\n\n"; while (<DATA>) { chomp; /$regex/ && printf "%-30smatched: %s\n", $_, $1; } __DATA__ roger@www.foo.com# blah roger@www.foo~ crap crap [roger@www#] blah blah foo [roger@www.foo~] crap crap \[\e[0m\] [0m foo bar

And the output -
regex: /(\[?[\w@\-\.]*[>$%@~# ]\]?|\\\[\\e\[0m\\\]\ \[0m)\s?/ roger@www.foo.com# blah matched: roger@www.foo.com# roger@www.foo~ crap crap matched: roger@www.foo~ [roger@www#] blah blah foo matched: [roger@www#] [roger@www.foo~] crap crap matched: [roger@www.foo~] \[\e[0m\] [0m foo bar matched: \[\e[0m\] [0m


In reply to Re: regex logical equivalence? by Roger
in thread regex logical equivalence? by Anonymous Monk

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