I wrote this method to apply a void function to a value and return the value.
public inline fun <T> T.apply(f: (T) -> Unit): T {
f(this)
return this
}
This is useful in reducing something like this:
return values.map {
var other = it.toOther()
doStuff(other)
return other
}
To something like this:
return values.map { it.toOther().apply({ doStuff(it) }) }
Is there a language feature or method like this already build in to Kotlin?
I ran into the same problem. My solution is basicly the same as yours with a small refinement:
inline fun <T> T.apply(f: T.() -> Any): T {
this.f()
return this
}
Note, that f is an extension function. This way you can invoke methods on your object using the implicit this reference. Here's an example taken from a libGDX project of mine:
val sprite : Sprite = atlas.createSprite("foo") apply {
setSize(SIZE, SIZE)
setOrigin(SIZE / 2, SIZE / 2)
}
Of course you could also call doStuff(this).
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