What's wrong with doing ... 
$self->{'content'} =~ s/foo/bar/g;

[download]
... you know just don't use the get_set method.
update Added tested code. 
Plankton@Chum_Bucket:~/perl/perlmonks> cat test.pl
#!/usr/local/bin/perl -w
use strict;
 
package Test;
 
sub new{
    my( $class, $value ) = @_;
    return bless { content => $value }, $class;
}
 
1;
 
package main;
 
my $thing = Test->new( 'empty' );
print $thing->{'content'} . "\n";
 
$thing->{'content'} = 'the quick brown fox';
print $thing->{'content'} . "\n";
 
$thing->{'content'} =~ s[\b(.)][\U$1]g;
print $thing->{'content'} . "\n";
Plankton@Chum_Bucket:~/perl/perlmonks> ./test.pl
empty
the quick brown fox
The Quick Brown Fox

[download]

Plankton: 1% Evil, 99% Hot Gas.

In reply to Re: regex transforms of object attributes by Plankton
in thread regex transforms of object attributes by Tuppence

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