| // run |
| |
| // Copyright 2021 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| package main |
| |
| import ( |
| "fmt" |
| "reflect" |
| ) |
| |
| type G[T any] interface { |
| g() func()(*T) |
| } |
| type Foo[T any] struct { |
| |
| } |
| // OCALL |
| func (l *Foo[T]) f1() (*T) { |
| return g[T]()() |
| } |
| // OCALLFUNC |
| func (l *Foo[T]) f2() (*T) { |
| var f = g[T] |
| return f()() |
| } |
| // OCALLMETH |
| func (l *Foo[T]) f3() (*T) { |
| return l.g()() |
| } |
| // OCALLINTER |
| func (l *Foo[T]) f4() (*T) { |
| var g G[T] = l |
| return g.g()() |
| } |
| // ODYNAMICDOTTYPE |
| func (l *Foo[T]) f5() (*T) { |
| var x interface{} |
| x = g[T] |
| return x.(func()func()(*T))()() |
| } |
| func (l *Foo[T]) g() func() (*T) { |
| return func() (*T) { |
| t := new(T) |
| reflect.ValueOf(t).Elem().SetInt(100) |
| return t |
| } |
| } |
| func g[T any]() func() (*T) { |
| return func() (*T) { |
| t := new(T) |
| reflect.ValueOf(t).Elem().SetInt(100) |
| return t |
| } |
| } |
| |
| func main() { |
| foo := Foo[int]{} |
| // Make sure the function conversion is correct |
| if n := *(foo.f1()) ; n != 100{ |
| panic(fmt.Sprintf("%v",n)) |
| } |
| if n := *(foo.f2()) ; n != 100{ |
| panic(fmt.Sprintf("%v",n)) |
| } |
| if n := *(foo.f3()) ; n != 100{ |
| panic(fmt.Sprintf("%v",n)) |
| } |
| if n := *(foo.f4()) ; n != 100{ |
| panic(fmt.Sprintf("%v",n)) |
| } |
| if n := *(foo.f5()) ; n != 100{ |
| panic(fmt.Sprintf("%v",n)) |
| } |
| } |