I have a question about what is more efficient for a small lookup function with only a few thousand items. Specifically I have a function in a module and that module has a function which gets passed a string. The function needs to determine if that string is in a set of a few thousand strings or not. How is that done most efficiently, and does the "best" approach vary by scale?

One way might be to load a hash with the strings as keys, and then see if defined($hash{$string}) or if defined($hash{$string}) has a value set.

Another would be to have a chain of elsif statements, and have the function cascade through those until either the end is reached or a match has been found.

Which approach is more appropriate or efficient? Or are the better approaches which can be used?

In reply to Hash versus chain of elsifs by mldvx4

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