content/slices/prog030.go


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// +build OMIT

// Copyright 2013 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"
)

var buffer [256]byte
var slice []byte = buffer[100:150]

func PtrSubtractOneFromLength(slicePtr *[]byte) {
	slice := *slicePtr
	*slicePtr = slice[0 : len(slice)-1]
}

func main() {
	fmt.Println("Before: len(slice) =", len(slice))
	PtrSubtractOneFromLength(&slice)
	fmt.Println("After:  len(slice) =", len(slice))
}