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5355753009
We don't usually reformat the test directory, but all of the files in test/typeparam are syntactically valid. I suspect the misformattings here are because developers aren't re-installing gofmt with -tags=typeparams, not intentionally exercising non-standard formatting. Change-Id: I3767d480434c19225568f3c7d656dc8589197183 Reviewed-on: https://go-review.googlesource.com/c/go/+/338093 Trust: Matthew Dempsky <mdempsky@google.com> Trust: Robert Griesemer <gri@golang.org> Run-TryBot: Matthew Dempsky <mdempsky@google.com> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Robert Griesemer <gri@golang.org>
61 lines
1.2 KiB
Go
61 lines
1.2 KiB
Go
// 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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// This test illustrates how a type bound method (String below) can be implemented
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// either by a concrete type (myint below) or a instantiated generic type
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// (StringInt[myint] below).
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package main
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import (
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"fmt"
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"reflect"
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"strconv"
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)
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type myint int
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//go:noinline
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func (m myint) String() string {
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return strconv.Itoa(int(m))
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}
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type Stringer interface {
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String() string
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}
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func stringify[T Stringer](s []T) (ret []string) {
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for _, v := range s {
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ret = append(ret, v.String())
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}
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return ret
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}
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type StringInt[T any] T
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//go:noinline
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func (m StringInt[T]) String() string {
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return "aa"
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}
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func main() {
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x := []myint{myint(1), myint(2), myint(3)}
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got := stringify(x)
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want := []string{"1", "2", "3"}
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if !reflect.DeepEqual(got, want) {
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panic(fmt.Sprintf("got %s, want %s", got, want))
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}
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x2 := []StringInt[myint]{StringInt[myint](1), StringInt[myint](2), StringInt[myint](3)}
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got2 := stringify(x2)
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want2 := []string{"aa", "aa", "aa"}
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if !reflect.DeepEqual(got2, want2) {
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panic(fmt.Sprintf("got %s, want %s", got2, want2))
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}
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}
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