正则表达式，提前内容

package main

import (
    "regexp"
    "fmt"
)

const text = `My email is [email protected]
email1 is [email protected]
email2 is   [email protected]
email3 is [email protected]
`

func main() {
    re := regexp.MustCompile(`([a-zA-Z0-9]+)@([a-zA-Z0-9]+)(\.[a-zA-Z0-9.]+)`)

    math := re.FindAllStringSubmatch(text,-1)
    for _,m:=range math {
        fmt.Println(m)
    }


}