I'm trying match the following: '$ (a literal apostrophe followed by a literal dollar sign).

This is my attempt: 

if ($source =~ /'\$/s) {
  push @errors, "possible unescaped sql string";
}

[download]
...and it doesn't work. Trawling through man perlre mentions this but I don't understand the solution:
You cannot include a literal $ or @ within a \Q sequence. An unescaped $ or @ interpolates the corresponding variable, while escaping will cause the literal string \$ to be matched. You'll need to write something like m/\Quser\E\@\Qhost/.
What is the secret?

Thanks
Steve Woodcock

In reply to How can I match '$ (literally) by Anonymous Monk

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