go/test/typeparam/stringable.go
Matthew Dempsky e24977d231 all: avoid use of cmd/compile -G flag in tests
The next CL will remove the -G flag, effectively hard-coding it to its
current default (-G=3).

Change-Id: Ib4743b529206928f9f1cca9fdb19989728327831
Reviewed-on: https://go-review.googlesource.com/c/go/+/388534
Reviewed-by: Keith Randall <khr@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
2022-03-01 19:45:34 +00:00

46 lines
833 B
Go

// run
// Copyright 2021 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
import (
"fmt"
"strconv"
"strings"
)
type Stringer interface {
String() string
}
// StringableList is a slice of some type, where the type
// must have a String method.
type StringableList[T Stringer] []T
func (s StringableList[T]) String() string {
var sb strings.Builder
for i, v := range s {
if i > 0 {
sb.WriteString(", ")
}
sb.WriteString(v.String())
}
return sb.String()
}
type myint int
func (a myint) String() string {
return strconv.Itoa(int(a))
}
func main() {
v := StringableList[myint]{myint(1), myint(2)}
if got, want := v.String(), "1, 2"; got != want {
panic(fmt.Sprintf("got %s, want %s", got, want))
}
}