Try the same with $foo="$bar";. The thing is, single quotes will get the characters literally ($,b,a,r) but doubles will interpolate (w,h,a,t,e,v,e,r,_,b,a,r,_,w,a,s).

A regex reads a '$' as the end of the string or a variable to interpolate. However, with $foo you just get the literal ($,b,a,r) back, no matter if you use \Q or not. So: 

$_='Some string with $foo and bar';
$bar='bar';
$foo='$bar';
/$bar/ and print "$&\n";
/$foo/ and print "$&\n";
/\Q$foo\E/ and print "$\n";

[download]
Just prints one 'bar'. Take a look at perlre and perlop.

Cheers,

Jeroen
"We are not alone"(FZ)

In reply to Re: Regex Grumblings (Variable Interpolation) by jeroenes
in thread Regex Grumblings (Variable Interpolation) by tadman

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