I frequently find myself using hashes to modify the value of a variable when a hash entry exists, otherwise set it to something else. For example, if I'm looking for a name to go with an ID number, I'll check the hash for the ID number. If that fails, the name should be "unknown".

I traditionally have done something like this: my $var = $hash{'key'}; $var = "something" unless $var; although I have more recently switched to my $var = $hash{'key'} || "something";, which I like even better. However, I still find myself wondering if there is a more elegant solution.

So, I'm wondering, is there a way to alter the value returned if a hash lookup fails? or have I stumbled on the Best Solution to my problem?

In reply to Making a failed hash lookup return something other than undef by jpfarmer

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