| // run |
| |
| // Copyright 2022 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" |
| ) |
| |
| type Printer[T ~string] struct { |
| PrintFn func(T) |
| } |
| |
| func Print[T ~string](s T) { |
| fmt.Println(s) |
| } |
| |
| func PrintWithPrinter[T ~string, S interface { |
| ~struct { |
| ID T |
| PrintFn_ func(T) |
| } |
| PrintFn() func(T) |
| }](message T, obj S) { |
| obj.PrintFn()(message) |
| } |
| |
| func main() { |
| PrintWithPrinter( |
| "Hello, world.", |
| StructWithPrinter{ID: "fake", PrintFn_: Print[string]}, |
| ) |
| } |
| |
| type StructWithPrinter struct { |
| ID string |
| PrintFn_ func(string) |
| } |
| |
| // Field accesses through type parameters are disabled |
| // until we have a more thorough understanding of the |
| // implications on the spec. See issue #51576. |
| // Use accessor method instead. |
| |
| func (s StructWithPrinter) PrintFn() func(string) { |
| return s.PrintFn_ |
| } |