haskell - Writing lazy curried in scala with multiple parameters -


i'm writing code game exercise learn scala after getting acquainted haskell. started adt follows:

sealed class circle(x: double, y: double, r: double)  case class playercircle (x: double, y: double, r: double) extends circle(x, y, r)  case class aicircle (x: double, y: double, r: double) extends circle(x, y, r)

i'm trying write lazy, curried val follows (in haskell pseudocode):

addtoplayer :: playercircle -> circle -> playercircle addtoplayer (playercircle px py pr) (aicircle _ _ cr) = playercircle px py (pr + cr) addtoplayer player _ = player

i have following:

def addtoplayer (wcircle : circle) : playercircle = wcircle match {     case aicircle (_, _, wr) => copy(this.x, this.y, this.r + wr)     case _ => }

what necessary make function curried , lazy?

edit: i've googled answer haven't found article of use please me one.

here's curried function example:

def addtoplayer(c: circle, p: player) = ... actual code... def addtoplayer(c: circle) = p: player => addtoplayer(c, p)

then can this:

val partial = addtoplayer(c) val complete = partial(p)

this lazy because addtoplayer(c, p) isn't run until both parameters given.

hth.


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