Sounds like a potential Golf to me, but i have a few questions. by "preserve the original" i assume you mean preserve the case of the original... what if the old word was "ELEphant" and the new word is "donkey"?

as for faster ways to do it, i bet bitwise functions will come in useful here, since all capital letters are bitwise-and-equal to 64, and lowers are all bitwise-and-equal to 96.

In reply to Re: Substitute Question by Vynce
in thread Substitute Question by RiotTown

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