package main
import (
"regexp"
"fmt"
)
func main() {
var re = regexp.MustCompile(`(?m)(?<!\d[\s-])(?<!\d)4\d{3}(?![\s-]?\d)`)
var str = `For example: 4567 (match)
I have 4999 roses (match)
1234567 days are gone (no match)
My water supply account is 123 4567 89 (no match)
Howdy, my cell number is 123-4567-89 (no match)
no match for 123 4567`
for i, match := range re.FindAllString(str, -1) {
fmt.Println(match, "found at index", i)
}
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Golang, please visit: https://golang.org/pkg/regexp/