I'm sure I'm missing something blindingly obvious but I'll ask anyway.

This is the Do What I Mean version of my code: 

$s = '
<p>something something</p>
<h2>blah blah blah</h2>
<p>something something</p>
';

$before = '<h2>([^<]+)</h2>';
$after = '<h1>$1</h1>';

$s =~ s/$before/$after/;

print $s;

[download]
But it doesn't. DWIM that is.

I get 

<p>something something</p>
<h1>$1</h1>
<p>something something</p>

[download]

Is there a way to do this? 

$s =~ s/$before/eval{$after}/e;

[download]
doesn't work, and neither does 
$regex = 's!<h2>([^<]+)</h2>!<h1>$1</h1>!g';

$s =~ $regex;

[download]

($_='kkvvttuubbooppuuiiffssqqffssmmiibbddllffss')
 =~y~b-v~a-z~s;                             print

[download]

In reply to Supplying the RHS to a regex as a variable by Cody Pendant

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