package main
import (
"regexp"
"fmt"
)
func main() {
var re = regexp.MustCompile(`(?m)^(\d+)\r?\n(?!\*{1,}END\*{1,})`)
var str = `abc
1
2
3
4
5
***END***
abc
6
7
8
9
***END***
abc
10
11
12
***END***`
var substitution = "$1,"
fmt.Println(re.ReplaceAllString(str, substitution))
}
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/