If needs else branch in expression of type Unit

roschlau · June 6, 2018, 7:54am

I don’t think special treatment of if in such a special edge case is justified. Kotlin tries to push you toward immutability and reducing side effects, and a when expression with a Unit return type just screams “SIDE EFFECT”. Sure, a lot of the time you can’t avoid those cases, but I’m not sure the language should actively encourage them. I think having a little more verbosity in a case like this is quite acceptable, because it makes inadvertently creating side effects harder.

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If needs else branch in expression of type Unit

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