package main
import (
"regexp"
"fmt"
)
func main() {
var re = regexp.MustCompile(`(?m)^(?=[^\d\n]*\d)(\d+)?[^\d\n]*(?:\((\d*)\))?[^\d\n]*$`)
var str = `all valid combinations
123(456)
123
(456)
abc(456)
123(efg)
these are not valid
abc(efg)
abc
(efg)
`
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/