Scala pattern matching default -


lets want write following function using scala's pattern matching:

def foo(num: int): int = {     num match {         case 1 => 0         case x if x%2 == 0 => 1         case _ => _     } }

but of course compilation error line case _ => _

i know can solve changing line like: case x=>x, why scala's pattern matching doesn't allow me that? it's way me saying don't care what's there return it.

because doesn't make sense. case _ means "match , don't assign value symbol", should => _ mean? if don't care is, mean compiler can put in random value?

case x => x eagerly match everything , return same value. it's clear, concise, , same amount of characters want. reads can understand happening. literally translate "i don't care what's there, match , return it".


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