Without parens on the LHS you'll call grep in scalar context and get the number of matches returned.

Only 0 matches is false.

But you should really take reverse into consideration to create an inverted hash.

Cheers Rolf

(addicted to the Perl Programming Language and ☆☆☆☆ :)

In reply to Re^3: Hash search and returning by value by LanX
in thread Hash search and returning by value by Anonymous Monk

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