Source file test/typeparam/issue50690c.go

     1  // run
     2  
     3  // Copyright 2022 The Go Authors. All rights reserved.
     4  // Use of this source code is governed by a BSD-style
     5  // license that can be found in the LICENSE file.
     6  
     7  package main
     8  
     9  import (
    10  	"fmt"
    11  )
    12  
    13  type Printer[T ~string] struct {
    14  	PrintFn func(T)
    15  }
    16  
    17  func Print[T ~string](s T) {
    18  	fmt.Println(s)
    19  }
    20  
    21  func PrintWithPrinter[T ~string, S interface {
    22  	~struct {
    23  		ID       T
    24  		PrintFn_ func(T)
    25  	}
    26  	PrintFn() func(T)
    27  }](message T, obj S) {
    28  	obj.PrintFn()(message)
    29  }
    30  
    31  func main() {
    32  	PrintWithPrinter(
    33  		"Hello, world.",
    34  		StructWithPrinter{ID: "fake", PrintFn_: Print[string]},
    35  	)
    36  }
    37  
    38  type StructWithPrinter struct {
    39  	ID       string
    40  	PrintFn_ func(string)
    41  }
    42  
    43  // Field accesses through type parameters are disabled
    44  // until we have a more thorough understanding of the
    45  // implications on the spec. See issue #51576.
    46  // Use accessor method instead.
    47  
    48  func (s StructWithPrinter) PrintFn() func(string) {
    49  	return s.PrintFn_
    50  }
    51  

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