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// Copyright 2012 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.
// embedded types
package decls3
import "unsafe"
import "fmt"
// fields with the same name at the same level cancel each other out
func _() {
type (
T1 struct { X int }
T2 struct { X int }
T3 struct { T1; T2 } // X is embedded twice at the same level via T1->X, T2->X
)
var t T3
_ = t.X /* ERROR "ambiguous selector t.X" */
}
func _() {
type (
T1 struct { X int }
T2 struct { T1 }
T3 struct { T1 }
T4 struct { T2; T3 } // X is embedded twice at the same level via T2->T1->X, T3->T1->X
)
var t T4
_ = t.X /* ERROR "ambiguous selector t.X" */
}
func issue4355() {
type (
T1 struct {X int}
T2 struct {T1}
T3 struct {T2}
T4 struct {T2}
T5 struct {T3; T4} // X is embedded twice at the same level via T3->T2->T1->X, T4->T2->T1->X
)
var t T5
_ = t.X /* ERROR "ambiguous selector t.X" */
}
func _() {
type State int
type A struct{ State }
type B struct{ fmt.State }
type T struct{ A; B }
var t T
_ = t.State /* ERROR "ambiguous selector t.State" */
}
// Embedded fields can be predeclared types.
func _() {
type T0 struct{
int
float32
f int
}
var x T0
_ = x.int
_ = x.float32
_ = x.f
type T1 struct{
T0
}
var y T1
_ = y.int
_ = y.float32
_ = y.f
}
// Restrictions on embedded field types.
func _() {
type I1 interface{}
type I2 interface{}
type P1 *int
type P2 *int
type UP unsafe.Pointer
type T1 struct {
I1
* /* ERROR "cannot be a pointer to an interface" */ I2
* /* ERROR "cannot be a pointer to an interface" */ error
P1 /* ERROR "cannot be a pointer" */
* /* ERROR "cannot be a pointer" */ P2
}
// unsafe.Pointers are treated like regular pointers when embedded
type T2 struct {
unsafe /* ERROR "cannot be unsafe.Pointer" */ .Pointer
*/* ERROR "cannot be unsafe.Pointer" */ unsafe.Pointer /* ERROR "Pointer redeclared" */
UP /* ERROR "cannot be unsafe.Pointer" */
* /* ERROR "cannot be unsafe.Pointer" */ UP /* ERROR "UP redeclared" */
}
}
// Named types that are pointers.
type S struct{ x int }
func (*S) m() {}
type P *S
func _() {
var s *S
_ = s.x
_ = s.m
var p P
_ = p.x
_ = p.m /* ERROR "no field or method" */
_ = P.m /* ERROR "no field or method" */
}
// Borrowed from the FieldByName test cases in reflect/all_test.go.
type D1 struct {
d int
}
type D2 struct {
d int
}
type S0 struct {
A, B, C int
D1
D2
}
type S1 struct {
B int
S0
}
type S2 struct {
A int
*S1
}
type S1x struct {
S1
}
type S1y struct {
S1
}
type S3 struct {
S1x
S2
D, E int
*S1y
}
type S4 struct {
*S4
A int
}
// The X in S6 and S7 annihilate, but they also block the X in S8.S9.
type S5 struct {
S6
S7
S8
}
type S6 struct {
X int
}
type S7 S6
type S8 struct {
S9
}
type S9 struct {
X int
Y int
}
// The X in S11.S6 and S12.S6 annihilate, but they also block the X in S13.S8.S9.
type S10 struct {
S11
S12
S13
}
type S11 struct {
S6
}
type S12 struct {
S6
}
type S13 struct {
S8
}
func _() {
_ = struct{}{}.Foo /* ERROR "no field or method" */
_ = S0{}.A
_ = S0{}.D /* ERROR "no field or method" */
_ = S1{}.A
_ = S1{}.B
_ = S1{}.S0
_ = S1{}.C
_ = S2{}.A
_ = S2{}.S1
_ = S2{}.B
_ = S2{}.C
_ = S2{}.D /* ERROR "no field or method" */
_ = S3{}.S1 /* ERROR "ambiguous selector S3{}.S1" */
_ = S3{}.A
_ = S3{}.B /* ERROR "ambiguous selector S3{}.B" */
_ = S3{}.D
_ = S3{}.E
_ = S4{}.A
_ = S4{}.B /* ERROR "no field or method" */
_ = S5{}.X /* ERROR "ambiguous selector S5{}.X" */
_ = S5{}.Y
_ = S10{}.X /* ERROR "ambiguous selector S10{}.X" */
_ = S10{}.Y
}
// Borrowed from the FieldByName benchmark in reflect/all_test.go.
type R0 struct {
*R1
*R2
*R3
*R4
}
type R1 struct {
*R5
*R6
*R7
*R8
}
type R2 R1
type R3 R1
type R4 R1
type R5 struct {
*R9
*R10
*R11
*R12
}
type R6 R5
type R7 R5
type R8 R5
type R9 struct {
*R13
*R14
*R15
*R16
}
type R10 R9
type R11 R9
type R12 R9
type R13 struct {
*R17
*R18
*R19
*R20
}
type R14 R13
type R15 R13
type R16 R13
type R17 struct {
*R21
*R22
*R23
*R24
}
type R18 R17
type R19 R17
type R20 R17
type R21 struct {
X int
}
type R22 R21
type R23 R21
type R24 R21
var _ = R0{}.X /* ERROR "ambiguous selector R0{}.X" */