package main
import (
"regexp"
"fmt"
)
func main() {
var re = regexp.MustCompile(`(?m)\[b\](?!\w*.\[\/b\])`)
var str = `By purely mathematical reasoning it is possible [b]to demonstrate ([i]or[/i] [b]prove) a theorem which...
[b]There is little point ([i]or[/i] [b]sense) in listing all of the known amino acids.
Much of the gravel is used [b]"as is" ([i]соl.[/i]) for building roads.
Tuberculin test [b]is of doubtful value in the elderly since its interpretation is very difficult.
[b](As) viewed from the top ([i]or[/i] [b]from above) the insect's abdomen swings to the top as if it were a rudder.`
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/