go/doc/progs/slices.go
Shenghou Ma 5b7562dd6f doc/progs: use test/run.go for testing on Windows
cgo[1-4].go, go1.go couldn't be tested now
(cgo[1-4].go can only be tested when cgo is enabled, go1.go
contain a list of filenames in the current directory)

R=golang-dev, alex.brainman, rsc
CC=golang-dev
https://golang.org/cl/6218048
2012-09-03 03:49:03 +08:00

65 lines
1.2 KiB
Go

// compile
// Copyright 2012 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 (
"io/ioutil"
"regexp"
)
func AppendByte(slice []byte, data ...byte) []byte {
m := len(slice)
n := m + len(data)
if n > cap(slice) { // if necessary, reallocate
// allocate double what's needed, for future growth.
newSlice := make([]byte, (n+1)*2)
copy(newSlice, slice)
slice = newSlice
}
slice = slice[0:n]
copy(slice[m:n], data)
return slice
}
// STOP OMIT
// Filter returns a new slice holding only
// the elements of s that satisfy f()
func Filter(s []int, fn func(int) bool) []int {
var p []int // == nil
for _, i := range s {
if fn(i) {
p = append(p, i)
}
}
return p
}
// STOP OMIT
var digitRegexp = regexp.MustCompile("[0-9]+")
func FindDigits(filename string) []byte {
b, _ := ioutil.ReadFile(filename)
return digitRegexp.Find(b)
}
// STOP OMIT
func CopyDigits(filename string) []byte {
b, _ := ioutil.ReadFile(filename)
b = digitRegexp.Find(b)
c := make([]byte, len(b))
copy(c, b)
return c
}
// STOP OMIT
func main() {
// place holder; no need to run
}