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kotlinlang

It would be awesome if `when` expressions over a String with plenty of constant cases could be optimized somehow, e.g. by using tableswitches for 1st &amp; 2nd character (esp. if latin) or by using hashes.
Right now such cases will just repeatedly call `equals` which can be much slower.

For now I’m using a `HashMap` with `String` as key and a lambda as value but the lambdas will create a crazy amount of anonymous classes.
I’ve also tried a `HashMap` to `Int` and then use the `Int` for the `when` expression but for whatever reason that was slower :open_mouth:  Prbl. because of boxing.

We do have an optimization for `when` over strings where we switch on the hash code, and then compare the string with one of the patterns with that hash code. It’s basically the same as in Java. Can you provide an example where it doesn’t work?

Ah I see it now! A tableswitch before the equals checks, great :slightly_smiling_face:
I guess I’ve just overlooked it the first time, thanks!