1// Copyright 2020 The Go Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style 3// license that can be found in the LICENSE file. 4 5package generics 6 7func _[A, B any](a A, b B) int {} 8func _[T any](x, y T) T 9 10type T[P any] struct{} 11type T[P1, P2, P3 any] struct{} 12 13type T[P C] struct{} 14type T[P1, P2, P3 C] struct{} 15 16type T[P C[P]] struct{} 17type T[P1, P2, P3 C[P1, P2, P3]] struct{} 18 19func f[P any](x P) 20func f[P1, P2, P3 any](x1 P1, x2 P2, x3 P3) struct{} 21 22func f[P interface{}](x P) 23func f[P1, P2, P3 interface{ m1(P1); ~P2|~P3 }](x1 P1, x2 P2, x3 P3) struct{} 24func f[P any](T1[P], T2[P]) T3[P] 25 26func (x T[P]) m() 27func ((T[P])) m(x T[P]) P 28 29func _() { 30 type _ []T[P] 31 var _ []T[P] 32 _ = []T[P]{} 33} 34 35// type constraint literals with elided interfaces 36func _[P ~int, Q int | string]() {} 37func _[P struct{f int}, Q *P]() {} 38 39// various potentially ambiguous type parameter lists (issue #49482) 40type _[P *T,] struct{} 41type _[P T | T] struct{} 42type _[P T | T | T | T] struct{} 43type _[P *T, _ any] struct{} 44type _[P (*T),] struct{} 45type _[P (*T), _ any] struct{} 46type _[P (T),] struct{} 47type _[P (T), _ any] struct{} 48 49type _[P *struct{}] struct{} 50type _[P (*struct{})] struct{} 51type _[P ([]int)] struct{} 52 53// a type literal in an |-expression indicates a type parameter list (blank after type parameter list and type) 54type _[P *[]int] struct{} 55type _[P *T | T, Q T] struct{} 56type _[P *[]T | T] struct{} 57type _[P *T | T | T | T | ~T] struct{} 58type _[P *T | T | T | ~T | T] struct{} 59type _[P *T | T | struct{} | T] struct{} 60type _[P <-chan int] struct{} 61type _[P *T | struct{} | T] struct{} 62 63// a trailing comma always indicates a (possibly invalid) type parameter list (blank after type parameter list and type) 64type _[P *T,] struct{} 65type _[P *T | T,] struct{} 66type _[P *T | <-T | T,] struct{} 67 68// slice/array type declarations (no blank between array length and element type) 69type _ []byte 70type _ [n]byte 71type _ [P(T)]byte 72type _ [P((T))]byte 73type _ [P * *T]byte 74type _ [P * T]byte 75type _ [P(*T)]byte 76type _ [P(**T)]byte 77type _ [P * T - T]byte 78type _ [P * T - T]byte 79type _ [P * T | T]byte 80type _ [P * T | <-T | T]byte 81 82// equivalent test cases for potentially ambiguous type parameter lists, except 83// for function declarations there is no ambiguity (issue #51548) 84func _[P *T,]() {} 85func _[P *T, _ any]() {} 86func _[P (*T),]() {} 87func _[P (*T), _ any]() {} 88func _[P (T),]() {} 89func _[P (T), _ any]() {} 90 91func _[P *struct{}] () {} 92func _[P (*struct{})] () {} 93func _[P ([]int)] () {} 94 95func _ [P(T)]() {} 96func _ [P((T))]() {} 97func _ [P * *T]() {} 98func _ [P * T]() {} 99func _ [P(*T)]() {} 100func _ [P(**T)]() {} 101func _ [P * T]() {} 102 103func _[ 104 P *T, 105]() {} 106