That construct is tres-weird. I didn't even know it would work. Learn something new. :) I'd say, just use =~ like Dog intended. 

perl -wle '$str = "not junk"; $str !~ s/junk//g; print $str'
Useless use of not in void context at -e line 1.
not

perl -wle '$str = "not junk"; $str =~ s/junk//g; print $str'
not

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Update: the warning in 5.10 is a bit more informative than the one in 5.8 too: "Useless use of negative pattern binding (!~) in void context at -e line 1."

In reply to Re: Is there a better way of dealing with !~ and "Useless use of not in void context at" warnings? by Your Mother
in thread Is there a better way of dealing with !~ and "Useless use of not in void context at" warnings? by Plankton

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