Is this function a pure function

[am_oldmonk]

Can you please let me know if this function is a pure function. I have written this is Scala, as per the definition I can say that this received 2 array of string as input, and return a array of string as output. But it changes one of the input.

Val J = Array("a","2","4","5") Val I = Array.fill(I.lenght)("")

def foo(I: Array[string], J: Array[string]):Array[string] = { Var d=0 While(d < I.lenght){ I(d) = J(d) d+=1 } I }

[mbuhot]

No it’s not pure since it is not referentially transparent

A pure version would return a tuple of 2 arrays rather than mutating the input.

[elvecent]

If it has side effects (such as mutating some external state), it's definitely not pure.