Your $1 gets interpolated too early. What you really need is a templating system, but you can use the following in the meanwhile: 

sub foo {
    (my $text = $_[0]) =~ s/$_[1]/eval $_[2]/e;
    print $text;
}

foo("This is test 1\n", qr/test (.*)/, '"fish $1"');

[download]

(Insert notice of hazards of using eval EXPR here.)

In reply to Re: How do I pass $1 to s///? by ikegami
in thread How do I pass $1 to s///? by Anonymous Monk

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