ReplaceAll in go

go文档的https://golang.org/pkg/regexp/#Regexp.ReplaceAll里面说:

func (*Regexp) ReplaceAll func (re *Regexp) ReplaceAll(src, repl []byte) []byte ReplaceAll returns a copy of src, replacing matches of the Regexp with the replacement text repl. Inside repl, $ signs are interpreted as in Expand, so for instance $1 represents the text of the first submatch.

p, _ = regexp.Compile("(a+)")
b = p.ReplaceAll([]byte("baabaaa"), []byte(`$1`))
glog.Infof("%s\n", b)
b = p.ReplaceAll([]byte("baabaaa"), []byte("xyz"))
glog.Infof("%s\n", b)

结果如下:

baabaaa
bxyzbxyz

Split也和我想像的不一样

s := regexp.MustCompile("a*").Split("abaabaccadaaae", 5)
// s: ["", "b", "b", "c", "cadaaae"]