PHP function to run a function (based on string)?
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Is there a PHP function or command that runs a function based on a string, array, or similar? Basically, if the string "time" is passed, I want `time()` to be returned. Ideally, I'd like this to also support passed parameters. I just want this to be for individual functions, though. I DON'T want to `eval()` an entire block of code, for obvious reasons.

Does anything like this exist--or, preferably--is it native in PHP?