package gapr import ( "strings" "unicode" ) type KeyMapper interface { MapKey(orig string) string } type KeyMapperFunc func(orig string) string func (f KeyMapperFunc) MapKey(orig string) string { return f(orig) } var ( LowercaseKeyMapper KeyMapper = KeyMapperFunc(func(orig string) string { return strings.ToLower(orig) }) UppercaseKeyMapper KeyMapper = KeyMapperFunc(func(orig string) string { return strings.ToUpper(orig) }) CamelCaseKeyMapper = genericFirstKeyMapper(unicode.ToLower) PascalCaseKeyMapper = genericFirstKeyMapper(unicode.ToUpper) ) func genericFirstKeyMapper(m func(r rune) rune) KeyMapper { return KeyMapperFunc(func(orig string) string { if len(orig) < 1 { return "" } mapped := make([]byte, 1, len(orig)) mapped[0] = byte(m(rune(orig[0]))) if len(orig) > 1 { mapped = append(mapped, orig[1:]...) } return string(mapped) }) }