mirror of
https://github.com/golang/go
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53 lines
915 B
Go
53 lines
915 B
Go
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// run -gcflags=-G=3
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// Copyright 2021 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Test wrappers/interfaces for generic type embedding another generic type.
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package main
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import "fmt"
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type A[T any] struct {
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B[T]
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}
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type B[T any] struct {
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val T
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}
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func (b *B[T]) get() T {
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return b.val
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}
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type getter[T any] interface {
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get() T
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}
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//go:noinline
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func doGet[T any](i getter[T]) T {
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return i.get()
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}
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//go:noline
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func doGet2[T any](i interface{}) T {
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i2 := i.(getter[T])
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return i2.get()
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}
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func main() {
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a := A[int]{B: B[int]{3}}
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var i getter[int] = &a
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if got, want := doGet(i), 3; got != want {
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panic(fmt.Sprintf("got %v, want %v", got, want))
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}
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as := A[string]{B: B[string]{"abc"}}
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if got, want := doGet2[string](&as), "abc"; got != want {
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panic(fmt.Sprintf("got %v, want %v", got, want))
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}
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}
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