If $value can be undefined, your check will be testing for the wrong thing. Use exists instead of defined.

But that's still klunky. Instead try

push @{ $hash{ $key } }, $value;

[download]

Now the value for each key will be an array reference containing all the different values.

Makeshifts last the longest.

In reply to Re: incrementing hash values by Aristotle
in thread incrementing hash values by Anonymous Monk

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