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How do I check to see if a value in a hash is equal to something?

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Contributed by Anonymous Monk on May 23, 2000 at 19:24 UTC
Q&A  > hashes


Something of this nature: if ((a value from %hash) eq "Superman"){ do something..; }

Answer: How do I check to see if a value in a hash is equal to something?
contributed by ZZamboni

One way would be by inverting the hash and looking things up by value, as described in perlman:perlfaq4 (see How do I look up a hash element by value?).

Another way, of you are only interested in knowing if the value is in the hash, without knowing the key, could be:

$is_in_hash=grep /^Superman$/,values(%hash);
This is not particularly space efficient if the hash is large. See also the second solution suggested in the FAQ mentioned above.


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