How do I apply switches to a precompiled (qr) regexp.

This code does not work: 

$regexp = qr/^(get|post)\b/; "GET / HTTP/1.1"=~m/$regexp/i and print "
+match\n";

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Originally posted as a Categorized Question.

In reply to How do I apply switches like /i or /g to a qr regexp? by ambrus

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