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Re^3: qr// and user provided regex patterns...

by ikegami (Pope)
on Aug 04, 2009 at 03:24 UTC ( #785631=note: print w/ replies, xml ) Need Help??


in reply to Re^2: qr// and user provided regex patterns...
in thread qr// and user provided regex patterns...

  • It makes no sense to let the user specify /g for a match. You can't even use it on qr// because it makes no sense. ixsm are the four modifiers that apply to the pattern as opposed to the operator.

  • The followign doesn't make much sense:

    my $compd_pattern = eval "qr($pattern)" or die $@;

    It removes the ability of qr// to quote, which is what you want. The code should be

    my $compd_pattern = qr($pattern);
  • You say you have problems doing substitutions, but you didn't show us your attempt (despite your claim). You should have no problems using a qr// pattern in a substitution.

my $pat = ...; my $repl = ...; my $mods = ''; $mods .= 'i' if ...; $mods .= 's' if ...; $mods .= 'm' if ...; $mods .= 'x' if ...; my $re = qr/(?$mods:$pat)/; if (...) { s/$re/$repl/g; } else { s/$re/$repl/; }


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Re^4: qr// and user provided regex patterns...
by JadeNB (Chaplain) on Aug 04, 2009 at 13:49 UTC
    You say you have problems doing substitutions, but you didn't show us your attempt (despite your claim). You should have no problems using a qr// pattern in a substitution.
    I think that misterMatt's problem was that he was trying to stuff a substitution into a qr//, like:
    my $substitution = 's/out/in/'; my $pattern = qr/$substitution/;
    which, naturally, doesn't work (well, doesn't cause a substitution, anyway).

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