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Re^2: Swap foo and bar in text?

by Jim (Curate)
on Apr 20, 2012 at 07:17 UTC ( #966113=note: print w/replies, xml ) Need Help??

in reply to Re: Swap foo and bar in text?
in thread Swap foo and bar in text?

Assuming "foo" and "bar" are metasyntactic variables, and that the real substrings could be anything, the use of quotemeta is in order:

UPDATE: This paragraph should readů

Assuming "foo" and "bar" are metasyntactic variables representing literal substrings, and that the real literal substrings could be any literal substrings (not regular expression patterns), then the use of quotemeta is in order:
#!/usr/bin/perl use strict; use warnings; my %edits = ( '***' => 'stars', '|||' => 'stripes' ); my $value = '*** and |||'; my $match = '(' . join('|', map { quotemeta } keys %edits) . ')'; $value =~ s/$match/$edits{$1}/g; print $value; # Prints "stars and stripes"

(I realize this example is no longer swapping anything. Sorry.)


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Re^3: Swap foo and bar in text?
by GrandFather (Sage) on Apr 20, 2012 at 08:33 UTC
    the real substrings could be anything

    Indeed, which is why I removed the quote meta code from the example code before posting it - anything could include regular expressions which don't work so well when quoted.

    True laziness is hard work

      I don't understand what you're saying. Why did you remove quotemeta? Isn't it necessary as a precaution?

      Never mind. I figured out what you're saying.


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