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//===--- generic_subscript.swift ------------------------------------------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
// RUN: %target-run-simple-swift
// REQUIRES: executable_test
//
import StdlibUnittest
var GenericSubscriptTestSuite = TestSuite("GenericSubscript")
struct S<T> : P {
typealias Element = T
var t: T
subscript<U>(a: (T) -> U, b: (U) -> T) -> U {
get {
print(T.self)
print(U.self)
return a(t)
}
set {
print(T.self)
print(U.self)
t = b(newValue)
}
}
}
protocol P {
associatedtype Element
subscript<U>(a: (Element) -> U, b: (U) -> Element) -> U { get set }
}
func increment<T : P>(p: inout T) where T.Element == String {
p[{Int($0)!}, {String($0)}] += 1
}
GenericSubscriptTestSuite.test("Basic") {
var s = S<String>(t: "0")
increment(p: &s)
expectEqual(s.t, "1")
}
protocol AnySubscript {
subscript(k: AnyHashable) -> Any? { get set }
}
struct AnyDictionary : AnySubscript {
var dict: [AnyHashable : Any] = [:]
subscript(k: AnyHashable) -> Any? {
get {
return dict[k]
}
set {
dict[k] = newValue
}
}
}
extension AnySubscript {
subscript<K : Hashable, V>(k k: K) -> V? {
get {
return self[k] as! V?
}
set {
self[k] = newValue
}
}
}
GenericSubscriptTestSuite.test("ProtocolExtensionConcrete") {
var dict = AnyDictionary()
func doIt(dict: inout AnyDictionary) {
dict["a" ] = 0
dict[k: "a"]! += 1
}
doIt(dict: &dict)
expectEqual(dict["a"]! as! Int, 1)
expectEqual(dict[k: "a"]!, 1)
}
GenericSubscriptTestSuite.test("ProtocolExtensionAbstract") {
var dict = AnyDictionary()
func doIt<T : AnySubscript>(dict: inout T) {
dict["a" ] = 0
dict[k: "a"]! += 1
}
doIt(dict: &dict)
expectEqual(dict["a"]! as! Int, 1)
expectEqual(dict[k: "a"]!, 1)
}
protocol GenericSubscript : AnySubscript {
subscript<K : Hashable, V>(k k: K) -> V? { get set }
}
extension AnyDictionary : GenericSubscript { }
GenericSubscriptTestSuite.test("ProtocolExtensionWitness") {
var dict = AnyDictionary()
func doIt<T : GenericSubscript>(dict: inout T) {
dict["a" ] = 0
dict[k: "a"]! += 1
}
doIt(dict: &dict)
expectEqual(dict["a"]! as! Int, 1)
expectEqual(dict[k: "a"]!, 1)
}
runAllTests()
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