You cannot avoid using a different variable.

The usual idiom is: 

    ($tmp = $string) =~ s/foo/blah/;

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If you want to combine it with calling a function, use Perls do: 
    func do {(my $tmp = $string) =~ s/foo/blah; $tmp};

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Or 
    func do {local $_ = $string; s/foo/blah; $_};

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-- Abigail

In reply to Re: Non-destructive substitution? by Abigail
in thread Non-destructive substitution? by Sprad

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