CODEWITHSUNDEEP
scala
Yann Moisan
Yann Moisan

Reputation: 8281

Reduce boilerplate with function composition

I have the following code :

def a = f(aa)
def b = f(bb)
def c = f(cc)
def d = f(dd)

Is there a solution to remove the boilerplate, i.e. explicit call to f

Upvotes: 0

Views: 135

Answers (2)

Kristian Domagala
Kristian Domagala

Reputation: 3696

You could do something like this with the standard library:

val List(a,b,c,d) = List(aa,bb,cc,dd).map(f)

It uses pattern matching to assign the values on the left, which will fail at runtime if the two Lists aren't the same length.

Scalaz has a more type-safe option that uses tuples to ensure the number of values on the left and right are the same (checked at compile time):

import scalaz._, Scalaz._
val (a,b,c,d) = (aa,bb,cc,dd).map(f)

Upvotes: 6

Rado Buransky
Rado Buransky

Reputation: 3294

You can use implicit: http://docs.scala-lang.org/overviews/core/implicit-classes.html

val aa: Int = 1

// Let's say that your function f returns instance of C
def f(x: Int): C = ???

implicit class C(in: Int) {
  // Do whatever you need here ...
}

def a: C = aa

Upvotes: 1

Related Questions