go/test/clear.go
Cuong Manh Le b89a840d65 cmd/compile: add clear(x) builtin
To clear map, and zero content of slice.

Updates #56351

Change-Id: I5f81dfbc465500f5acadaf2c6beb9b5f0d2c4045
Reviewed-on: https://go-review.googlesource.com/c/go/+/453395
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2023-01-31 19:43:07 +00:00

47 lines
743 B
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
import "math"
func checkClearSlice() {
s := []int{1, 2, 3}
clear(s)
for i := range s {
if s[i] != 0 {
panic("clear not zeroing slice elem")
}
}
clear([]int{})
}
func checkClearMap() {
m1 := make(map[int]int)
m1[0] = 0
m1[1] = 1
clear(m1)
if len(m1) != 0 {
panic("m1 is not cleared")
}
// map contains NaN keys is also cleared.
m2 := make(map[float64]int)
m2[math.NaN()] = 1
m2[math.NaN()] = 1
clear(m2)
if len(m2) != 0 {
panic("m2 is not cleared")
}
clear(map[int]int{})
}
func main() {
checkClearSlice()
checkClearMap()
}