Decompile regexes made with qr//
# Thanks go to Arien for simplifying and enhancing :)
sub deregex {
    my $regex = shift;
    my ($ops, $pat) = $regex =~ /^\(\? ([msix-]+) : (.*) \)$/x
        or die "Unknown qr// format";

    $pat =~ s!/!\\/!g;
    $ops =~ s/-.*//;
    return "/$pat/$ops";
}

[download]

Replies are listed 'Best First'.
Re: Deregex
by Arien (Pilgrim) on Aug 30, 2002 at 23:00 UTC

    You're missing a $ in my (regex) = @_. Also, you can qr// an empty string, which will break your regex.

    Simplifying and enhancing a bit more results in something like:

    sub deregex {
    my $regex = shift;
    my ($ops, $pat) = $regex =~ /^\(\? ([msix-]+) : (.*) \)$/x
        or die "Unknown qr// format";

    $pat =~ s!/!\\/!g;
    $ops =~ s/-.*//;
    return "/$pat/$ops";
}

    [download]

    — Arien

[reply]
[d/l]
[select]
      Oopsy. I must've removed it when I removed the $self, from it (It was a method). Thanks a lot!
[reply]
[d/l]
Re: Deregex
by belg4mit (Prior) on Aug 31, 2002 at 01:10 UTC
    But a qr already stringifies as a valid regexp. Unless your intent is to make something which can be passed back into qr, which is not the same thing, but that doesn't seem to be the case.

    --
    perl -pew "s/\b;([mnst])/'$1/g"

[reply]
      It's for error messages, actually. "... doesn't match ..." type thing.
[reply]

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