Function isWordByte

regexp/match.go:344–349

isWordByte reports whether the byte c is a word character: ASCII only. This is used to implement \b and \B. This is not right for Unicode, but: - it's hard to get right in a byte-at-a-time matching world (the DFA has only one-byte lookahead) - this crude approximation is the same one PCRE uses

(c int)

//	  (the DFA has only one-byte lookahead)
//	- this crude approximation is the same one PCRE uses
func isWordByte(c int) bool {
	return 'A' <= c && c <= 'Z' ||
		'a' <= c && c <= 'z' ||
		'0' <= c && c <= '9' ||
		c == '_'
}

// TODO:
type Grep struct {