tags - Canonical way to work on Option elements in Scala -


as example, want apply function f: (int,int) => int 2 elements of type option[int]. thoughts (a,b).zipped.map(f), yields list, , want new option[int] result.

scala> def f(a:int,b:int) = a*b f: (a: int, b: int)int  scala> val x = some(42) x: some[int] = some(42)  scala> val y:option[int] = none y: option[int] = none  scala> (x,y).zipped.map(f)//i want none result here res7: iterable[int] = list()

how can done without explicitly branching?

just many other operations in scala can done via comprehension:

def f(a:int,b:int) = a*b (x <- maybex; y <- maybey) yield f(x, y)

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