scalapartial-functions

How to take a constant Integer as input in Partial Function?

I am new to scala, I have a use case where I want to define a partial function to add three numbers in which one number is constant and two numbers can be passed as inputs and define another method which can take the partial function as input and gives its cube as result.

Solution

  • The following partial function adds 12345 to each number in the tuple passed to it

    scala> val addConstantTo: PartialFunction[(Int, Int), Int] = {
     |   case (a, b) => a + b + 12345
     | }
addConstantTo: PartialFunction[(Int, Int),Int] = <function1>

scala> addConstantTo((12, 34))
res4: Int = 12391

    This expands on the concept, by programmatically defining a partial function which adds any number to the elements of a tuple:

    scala> def addTo(c: Int): PartialFunction[(Int, Int), Int] = {
     |   case (a, b) => a + b + c
     | }
addTo: (c: Int)PartialFunction[(Int, Int),Int]

scala> val pf = addTo(3)
pf: PartialFunction[(Int, Int),Int] = <function1>

scala> pf((1, 2))
res5: Int = 6

    Let that sink in for a bit :)