Function1 (original) (raw)
scala.Function1
See theFunction1 companion object
A function of 1 parameter.
In the following example, the definition of succ is shorthand, conceptually, for the anonymous class definition anonfun1, although the implementation details of how the function value is constructed may differ:
object Main extends App {
val succ = (x: Int) => x + 1
val anonfun1 = new Function1[Int, Int] {
def apply(x: Int): Int = x + 1
}
assert(succ(0) == anonfun1(0))
}
Note that the difference between Function1 and scala.PartialFunction is that the latter can specify inputs which it will not handle.
Attributes
Companion
Source
Graph
Supertypes
Known subtypes
class From <:< To
class From =:= To
trait MapOps[K, V, CC, C]
trait MapOps[K, V, CC, C]
trait Map[K, V]
trait MapOps[K, V, CC, C]
trait Map[K, V]
trait Map[K, V]
trait Map[K, V]
class Id[K, V]
class ::[A]
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Self type
Members list
Apply the body of this function to the argument.
Apply the body of this function to the argument.
Attributes
Returns
the result of function application.
Source
Composes two instances of Function1 in a new Function1, with this function applied first.
Composes two instances of Function1 in a new Function1, with this function applied first.
Type parameters
A
the result type of function g
Value parameters
g
a function R => A
Attributes
Returns
a new function f such that f(x) == g(apply(x))
Source
Composes two instances of Function1 in a new Function1, with this function applied last.
Composes two instances of Function1 in a new Function1, with this function applied last.
Type parameters
A
the type to which function g can be applied
Value parameters
g
a function A => T1
Attributes
Returns
a new function f such that f(x) == apply(g(x))
Source
Returns a string representation of the object.
Returns a string representation of the object.
The default representation is platform dependent.
Attributes
Returns
a string representation of the object.
Definition Classes
Source
Converts an optional function to a partial function.
Converts an optional function to a partial function.
Attributes
Example
Unlike Function.unlift, this UnliftOps.unlift method can be used in extractors.
val of: Int => Option[String] = { i =>
if (i == 2) {
Some("matched by an optional function")
} else {
None
}
}
util.Random.nextInt(4) match {
case of.unlift(m) => // Convert an optional function to a pattern
println(m)
case _ =>
println("Not matched")
}
Source
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