const regexp/syntax.OpNoMatch

5 uses

	regexp/syntax (current package)
		compile.go#L91: 	case OpNoMatch:
		parse.go#L384: 		return p.push(p.newRegexp(OpNoMatch))
		regexp.go#L39: 	OpNoMatch        Op = 1 + iota // matches no strings
		regexp.go#L120: 	case OpNoMatch:
		simplify.go#L113: 		return &Regexp{Op: OpNoMatch}