Re: Replace after match in regex (key value subsitution)

The following eg. code will substitute the '%fixers' hash key with corresponding value from '$text'.

#!/usr/bin/perl -w
use strict;

my %fixers=(
    'amazon.com' => 'danube.com',
    'ibm.com'    => 'bm.com',
    );

my $text = qq(
Blah <a href="http://amazon.com/foo">one</a>
     <a href="http://ebay.com/foo">two</a>
);

map {
  $text =~ s/$_/$fixers{$_}/;
}keys %fixers;

print $text;
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Comment on Re: Replace after match in regex (key value subsitution) Download Code

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Re^2: Replace after match in regex (key value subsitution) by ikegami (Patriarch) on Oct 23, 2008 at 04:28 UTC
Almost. You forgot to convert the text to a regexp pattern. You only replace the first instance. And since I'm already changing the line, I'll remove the useless use of `map`. `$text =~ s/\Q$_\E/$fixers{$_}/g for keys %fixers;` [download] It could still be improved if it's going to be done repeatedly. `my ($re) = map qr/$_/, join '\|', map quotemeta, keys %fixers; while (...) { ... $text =~ s/$re/$fixers{$_}/g for keys %fixers; ... }` [download] Or even better for pre-5.10 `use List::Regexp qw( ); my $re = List::Regexp->new()->list2re( keys %fixers ); while (...) { ... $text =~ s/$re/$fixers{$_}/g for keys %fixers; ... }` [download]	[reply] [d/l] [select]

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Re^2: Replace after match in regex (key value subsitution)
by ikegami (Patriarch) on Oct 23, 2008 at 04:28 UTC

You forgot to convert the text to a regexp pattern.
You only replace the first instance.
And since I'm already changing the line, I'll remove the useless use of map.

$text =~ s/\Q$_\E/$fixers{$_}/g
   for keys %fixers;
[download]

It could still be improved if it's going to be done repeatedly.

my ($re) = map qr/$_/,
           join '|',
           map quotemeta,
           keys %fixers;

while (...) {
   ...
   $text =~ s/$re/$fixers{$_}/g
      for keys %fixers;
   ...
}
[download]

Or even better for pre-5.10

use List::Regexp qw( );

my $re = List::Regexp->new()->list2re( keys %fixers );

while (...) {
   ...
   $text =~ s/$re/$fixers{$_}/g
      for keys %fixers;
   ...
}
[download]

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