func compile()

in match/compile.go [25:83]

• 48 lines of code
• 15 McCabe index (conditional complexity)

func compile(r *syntax.Regexp) (stringMatcher, error) {
	switch {
	case isSubstringLiteral(r):
		s := string(r.Rune)
		return &substringMatcher{s, []byte(s)}, nil

	case isExactLiteral(r):
		s := string(r.Sub[1].Rune)
		return &equalsMatcher{s, []byte(s)}, nil

	case isAltLiterals(r):
		var literals [][]byte
		for _, sub := range r.Sub {
			literals = append(literals, []byte(string(sub.Rune)))
		}
		return &altSubstringMatcher{literals}, nil

	case isOneOfLiterals(r):
		var literals [][]byte
		for _, sub := range r.Sub[1].Sub {
			literals = append(literals, []byte(string(sub.Rune)))
		}
		return &oneOfMatcher{literals}, nil

	case isPrefixLiteral(r):
		s := []byte(string(r.Sub[1].Rune))
		return &prefixMatcher{s}, nil

	case isPrefixAltLiterals(r):
		var literals [][]byte
		for _, sub := range r.Sub[1].Sub {
			literals = append(literals, []byte(string(sub.Rune)))
		}
		return &altPrefixMatcher{literals}, nil

	case isPrefixNumDate(r):
		return compilePrefixNumDate(r)

	case isEmptyText(r):
		var m *emptyStringMatcher
		return m, nil

	case isEmptyTextWithWhitespace(r):
		var m *emptyWhiteStringMatcher
		return m, nil

	case isAnyMatch(r):
		var m *matchAny
		return m, nil

	default:

		r, err := regexp.Compile(r.String())
		if err != nil {
			return nil, err
		}
		return r, nil
	}
}