Perl hash keys are strings, and in most cases, you need to quote them whenever Perl does not recognize them as single words:

$hashTable{'%(Math_value)'} = "pi";

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As a quick rule, Perl will accept all ASCII words as an unquoted hash key that matche /^\w+$/.

In reply to Re: Hash Table - can special characters be stored as Keys? by Corion
in thread Hash Table - can special characters be stored as Keys? by pawel84

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