package main
import (
"regexp"
"fmt"
)
func main() {
var re = regexp.MustCompile(`(?m)(?:(?!\bCats\h+Dogs\b)\b\w+\h+\w+\h+)*?(?:^\h*|\b(?!Cats\b)\w+\h+)(Dogs)\b`)
var str = `My Dogs are happy
Dogs are humans best friend
This is invalid Cats Dogs
The Dogs and Cats and Dogs and Dogs
There are Dogs and Cats and Dogs and Cats Dogs
The TomCats Dogs are valid
Dogs Cats Dogs`
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/