The key is to copy the data you want to preserve. If you need this kind of behaviour very often, write a simple subroutine that does what you want.

sub cdo(&$){
    local $_ = $_[1];
    $_[0]->();
    $_
}

my $foo = 'abc';
print cdo { s/abc/def/ } $foo;
print "\n$foo\n";

[download]

TI, of course, MTOWTDI.

--
http://fruiture.de

In reply to Re: Non-destructive string substitution by fruiture
in thread Non-destructive string substitution by Sprad

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