mirror of
https://github.com/golang/go
synced 2024-09-05 07:54:46 +00:00
![Robert Griesemer](/assets/img/avatar_default.png)
This is a feature that is not understood well enough and may have subtle repercussions impacting future changes. Disable for Go 1.18. The actual change is trivial: disable a branch through a flag. The remaining changes are adjustments to tests. Fixes #51576. Change-Id: Ib77b038b846711a808315a8889b3904e72367bce Reviewed-on: https://go-review.googlesource.com/c/go/+/391135 Trust: Robert Griesemer <gri@golang.org> Run-TryBot: Robert Griesemer <gri@golang.org> Reviewed-by: Robert Findley <rfindley@google.com> TryBot-Result: Gopher Robot <gobot@golang.org>
147 lines
1.5 KiB
Go
147 lines
1.5 KiB
Go
// 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
|
|
|
|
func main() {}
|
|
|
|
// Field accesses through type parameters are disabled
|
|
// until we have a more thorough understanding of the
|
|
// implications on the spec. See issue #51576.
|
|
|
|
/*
|
|
type Sf struct {
|
|
f int
|
|
}
|
|
|
|
func f0[P Sf](p P) {
|
|
_ = p.f
|
|
p.f = 0
|
|
}
|
|
|
|
func f0t[P ~struct{ f int }](p P) {
|
|
_ = p.f
|
|
p.f = 0
|
|
}
|
|
|
|
var _ = f0[Sf]
|
|
var _ = f0t[Sf]
|
|
|
|
func f1[P interface {
|
|
~struct{ f int }
|
|
m()
|
|
}](p P) {
|
|
_ = p.f
|
|
p.f = 0
|
|
p.m()
|
|
}
|
|
|
|
var _ = f1[Sfm]
|
|
|
|
type Sm struct{}
|
|
|
|
func (Sm) m() {}
|
|
|
|
type Sfm struct {
|
|
f int
|
|
}
|
|
|
|
func (Sfm) m() {}
|
|
|
|
func f2[P interface {
|
|
Sfm
|
|
m()
|
|
}](p P) {
|
|
_ = p.f
|
|
p.f = 0
|
|
p.m()
|
|
}
|
|
|
|
var _ = f2[Sfm]
|
|
|
|
// special case: core type is a named pointer type
|
|
|
|
type PSfm *Sfm
|
|
|
|
func f3[P interface{ PSfm }](p P) {
|
|
_ = p.f
|
|
p.f = 0
|
|
}
|
|
|
|
var _ = f3[PSfm]
|
|
|
|
// special case: core type is an unnamed pointer type
|
|
|
|
func f4[P interface{ *Sfm }](p P) {
|
|
_ = p.f
|
|
p.f = 0
|
|
}
|
|
|
|
var _ = f4[*Sfm]
|
|
|
|
type A int
|
|
type B int
|
|
type C float64
|
|
|
|
type Int interface {
|
|
*Sf | A
|
|
*Sf | B
|
|
}
|
|
|
|
func f5[P Int](p P) {
|
|
_ = p.f
|
|
p.f = 0
|
|
}
|
|
|
|
var _ = f5[*Sf]
|
|
|
|
type Int2 interface {
|
|
*Sf | A
|
|
any
|
|
*Sf | C
|
|
}
|
|
|
|
func f6[P Int2](p P) {
|
|
_ = p.f
|
|
p.f = 0
|
|
}
|
|
|
|
var _ = f6[*Sf]
|
|
|
|
type Int3 interface {
|
|
Sf
|
|
~struct{ f int }
|
|
}
|
|
|
|
func f7[P Int3](p P) {
|
|
_ = p.f
|
|
p.f = 0
|
|
}
|
|
|
|
var _ = f7[Sf]
|
|
|
|
type Em1 interface {
|
|
*Sf | A
|
|
}
|
|
|
|
type Em2 interface {
|
|
*Sf | B
|
|
}
|
|
|
|
type Int4 interface {
|
|
Em1
|
|
Em2
|
|
any
|
|
}
|
|
|
|
func f8[P Int4](p P) {
|
|
_ = p.f
|
|
p.f = 0
|
|
}
|
|
|
|
var _ = f8[*Sf]
|
|
*/
|