Patch self type of Function1 and PartialFunction

Author: nicolasstucki

scala2-library-cc/src/scala/Function1.scala

@@ -0,0 +1,90 @@
+/*
+ * Scala (https://www.scala-lang.org)
+ *
+ * Copyright EPFL and Lightbend, Inc.
+ *
+ * Licensed under Apache License 2.0
+ * (http://www.apache.org/licenses/LICENSE-2.0).
+ *
+ * See the NOTICE file distributed with this work for
+ * additional information regarding copyright ownership.
+ */
+
+// GENERATED CODE: DO NOT EDIT. See scala.Function0 for timestamp.
+
+package scala
+
+
+object Function1 {
+
+  implicit final class UnliftOps[A, B] private[Function1](private val f: A => Option[B]) extends AnyVal {
+    /** Converts an optional function to a partial function.
+      *
+      * @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")
+      *          }
+      *          }}}
+      */
+    def unlift: PartialFunction[A, B] = Function.unlift(f)
+  }
+
+}
+
+/** 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.
+ */
+@annotation.implicitNotFound(msg = "No implicit view available from ${T1} => ${R}.")
+trait Function1[@specialized(Specializable.Arg) -T1, @specialized(Specializable.Return) +R] extends AnyRef { // FIXME: self =>
+  /** Apply the body of this function to the argument.
+   *  @return   the result of function application.
+   */
+  def apply(v1: T1): R
+
+  /** Composes two instances of Function1 in a new Function1, with this function applied last.
+   *
+   *  @tparam   A   the type to which function `g` can be applied
+   *  @param    g   a function A => T1
+   *  @return       a new function `f` such that `f(x) == apply(g(x))`
+   */
+  @annotation.unspecialized def compose[A](g: A => T1): A => R = { x => apply(g(x)) }
+
+  /** Composes two instances of Function1 in a new Function1, with this function applied first.
+   *
+   *  @tparam   A   the result type of function `g`
+   *  @param    g   a function R => A
+   *  @return       a new function `f` such that `f(x) == g(apply(x))`
+   */
+  @annotation.unspecialized def andThen[A](g: R => A): T1 => A = { x => g(apply(x)) }
+
+  override def toString(): String = "<function1>"
+}