Function specificity

caddyconfig/httpcaddyfile/httptype.go:1726–1741

specificity returns len(s) minus any wildcards (*) and placeholders ({...}). Basically, it's a length count that penalizes the use of wildcards and placeholders. This is useful for comparing hostnames and paths. However, wildcards in paths are not a sure answer to the question of specificity. For ex

(s string)

// 'a.example.com', but is '/a' more or less specific
// than '/a*'?
func specificity(s string) int {
	l := len(s) - strings.Count(s, "*")
	for len(s) > 0 {
		start := strings.Index(s, "{")
		if start < 0 {
			return l
		}
		end := strings.Index(s[start:], "}") + start + 1
		if end <= start {
			return l
		}
		l -= end - start
		s = s[end:]
	}
	return l
}

type counter struct {
	n *int