locale/lookup.go - exp - Git at Google

 // Copyright 2013 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.

 package locale

 import (
 	"fmt"
 	"sort"
 	"strconv"
 )

 // get gets the string of length n for id from the given 4-byte string index.
 func get(idx string, id, n int) string {
 	return idx[id<<2:][:n]
 }

 // search searchs for the insertion point of key in smap, which is a
 // string with consecutive 4-byte entries. Only the first len(key)
 // bytes from the start of the 4-byte entries will be considered.
 func search(smap, key string) int {
 	n := len(key)
 	return sort.Search(len(smap)>>2, func(i int) bool {
 		return get(smap, i, n) >= key
 	}) << 2
 }

 func index(smap, key string) int {
 	i := search(smap, key)
 	if smap[i:i+len(key)] != key {
 		return -1
 	}
 	return i
 }

 func searchUint(imap []uint16, key uint16) int {
 	return sort.Search(len(imap), func(i int) bool {
 		return imap[i] >= key
 	})
 }

 // fixCase reformats s to the same pattern of cases as pat.
 // If string s is malformed, pat is returned.
 func fixCase(pat, s string) string {
 	if len(pat) != len(s) {
 		return pat
 	}
 	var b []byte
 	for i, r := range pat {
 		c := s[i]
 		if r <= 'Z' {
 			if s[i] >= 'a' {
 				c -= 'z' - 'Z'
 			}
 			if c > 'Z' || c < 'A' {
 				return pat
 			}
 		} else {
 			if s[i] <= 'Z' {
 				c += 'z' - 'Z'
 			}
 			if c > 'z' || c < 'a' {
 				return pat
 			}
 		}
 		if b == nil {
 			if s[i] == c {
 				continue
 			}
 			b = make([]byte, len(pat))
 			copy(b, s[:i])
 		}
 		b[i] = c
 	}
 	if b == nil {
 		return s
 	}
 	return string(b)
 }

 type langID uint16

 // getLangID returns the langID of s if s is a canonical ID
 // or langUnknown if s is not a canonical langID.
 func getLangID(s string) langID {
 	if len(s) == 2 {
 		return getLangISO2(s)
 	}
 	return getLangISO3(s)
 }

 func getMappedID(index int) langID {
 	m := mappedLang[index:]
 	if m[3] >= 'a' {
 		return getLangISO2(m[:1] + m[3:4])
 	}
 	i := mappedLangID[m[3]]
 	if i < 0 {
 		i = -(i + 1)
 		// TODO: this code can be a locale.
 		return getLangISO2(altTag[i:][:2])
 	}
 	return langID(i)
 }

 // normLang returns the langID of s, canonicalizing the language
 // according to BCP47 and CLDR rules.
 func normLang(s string) langID {
 	s = getLangID(s).String()
 	if len(s) < 2 || len(s) > 3 {
 		return unknownLang
 	}
 	if i := index(mappedLang, s); i != -1 {
 		if len(s) == 3 || mappedLang[i+2] == ' ' {
 			return getMappedID(i)
 		}
 	}
 	return getLangID(s)
 }

 // getLangISO2 returns the langID for the given 2-letter ISO language code
 // or unknownLang if this does not exist.
 func getLangISO2(s string) langID {
 	if len(s) == 2 {
 		s = fixCase("zz", s)
 		if i := index(lang, s); i != -1 && lang[i+3] != 0 {
 			return langID(i >> 2)
 		}
 		if i := index(mappedLang, s); i != -1 && mappedLang[i+2] == ' ' {
 			return getMappedID(i)
 		}
 	}
 	return unknownLang
 }

 // getLangISO3 returns the langID for the given 3-letter ISO language code
 // or unknownLang if this does not exist.
 func getLangISO3(s string) langID {
 	s = fixCase("und", s)
 	// first try to match canonical 3-letter entries
 	for i := search(lang, s[:2]); lang[i:i+2] == s[:2]; i += 4 {
 		if lang[i+3] == 0 && lang[i+2] == s[2] {
 			return langID(i >> 2)
 		}
 	}
 	if i := index(mappedLang, s); i != -1 {
 		return getMappedID(i)
 	}
 	// Check for non-canonical uses of ISO3.
 	for i := search(lang, s[:1]); lang[i] == s[0]; i += 4 {
 		if lang[i+2:][:2] == s[1:3] {
 			return langID(i >> 2)
 		}
 	}
 	return unknownLang
 }

 // String returns the BCP47 representation of the langID.
 func (id langID) String() string {
 	l := lang[id<<2:]
 	if l[3] == 0 {
 		return l[:3]
 	}
 	return l[:2]
 }

 // ISO3 returns the ISO 639-3 language code.
 func (id langID) iso3() string {
 	l := lang[id<<2:]
 	if l[3] == 0 {
 		return l[:3]
 	} else if l[2] == 0 {
 		return get(mappedLang, int(l[3]), 3)
 	}
 	// This allocation will only happen for 3-letter ISO codes
 	// that are non-canonical BCP47 language identifiers.
 	return l[0:1] + l[2:4]
 }

 type regionID uint16

 // getRegionID returns the region id for s if s is a valid 2-letter region code
 // or unknownRegion.
 func getRegionID(s string) regionID {
 	if len(s) == 3 {
 		if s[0] >= 'A' {
 			return getRegionISO3(s)
 		}
 		if i, err := strconv.ParseUint(s, 10, 10); err == nil {
 			return getRegionM49(int(i))
 		}
 	}
 	return getRegionISO2(s)
 }

 // getRegionISO2 returns the regionID for the given 2-letter ISO country code
 // or unknownRegion if this does not exist.
 func getRegionISO2(s string) regionID {
 	if i := index(regionISO, fixCase("ZZ", s)); i != -1 {
 		return regionID(i>>2) + isoRegionOffset
 	}
 	return unknownRegion
 }

 // getRegionISO3 returns the regionID for the given 3-letter ISO country code
 // or unknownRegion if this does not exist.
 func getRegionISO3(s string) regionID {
 	s = fixCase("ZZZ", s)
 	for i := search(regionISO, s[:1]); regionISO[i] == s[0]; i += 4 {
 		if regionISO[i+2:][:2] == s[1:3] {
 			return regionID(i>>2) + isoRegionOffset
 		}
 	}
 	for i := 0; i < len(altRegionISO3); i += 3 {
 		if altRegionISO3[i:i+3] == s {
 			return regionID(altRegionIDs[i/3])
 		}
 	}
 	return unknownRegion
 }

 func getRegionM49(n int) regionID {
 	// These will mostly be group IDs, which are at the start of the list.
 	// For other values this may be a bit slow, as there are over 300 entries.
 	// TODO: group id is sorted!
 	if n == 0 {
 		return unknownRegion
 	}
 	for i, v := range m49 {
 		if v == uint16(n) {
 			return regionID(i)
 		}
 	}
 	return unknownRegion
 }

 // String returns the BCP47 representation for the region.
 func (r regionID) String() string {
 	if r < isoRegionOffset {
 		return fmt.Sprintf("%03d", r.m49())
 	}
 	r -= isoRegionOffset
 	return get(regionISO, int(r), 2)
 }

 // The use of this is uncommon.
 // Note: not all regionIDs have corresponding 3-letter ISO codes!
 func (r regionID) iso3() string {
 	if r < isoRegionOffset {
 		return ""
 	}
 	r -= isoRegionOffset
 	reg := regionISO[r<<2:]
 	switch reg[2] {
 	case 0:
 		return altRegionISO3[reg[3]:][:3]
 	case ' ':
 		return ""
 	}
 	return reg[0:1] + reg[2:4]
 }

 func (r regionID) m49() uint16 {
 	return m49[r]
 }

 type scriptID uint8

 // getScriptID returns the script id for string s. It assumes that s
 // is of the format [A-Z][a-z]{3}.
 func getScriptID(idx, s string) scriptID {
 	if i := index(idx, fixCase("Zzzz", s)); i != -1 {
 		return scriptID(i >> 2)
 	}
 	return unknownScript
 }

 func (s scriptID) String() string {
 	return get(script, int(s), 4)
 }

 type currencyID uint16

 func getCurrencyID(idx, s string) currencyID {
 	if i := index(idx, fixCase("XXX", s)); i != -1 {
 		return currencyID(i >> 2)
 	}
 	return unknownCurrency
 }

 func round(index string, c currencyID) int {
 	return int(index[c<<2+3] >> 2)
 }

 func decimals(index string, c currencyID) int {
 	return int(index[c<<2+3] & 0x03)
 }
	// Copyright 2013 The Go Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style
	// license that can be found in the LICENSE file.

	package locale

	import (
	"fmt"
	"sort"
	"strconv"
	)

	// get gets the string of length n for id from the given 4-byte string index.
	func get(idx string, id, n int) string {
	return idx[id<<2:][:n]
	}

	// search searchs for the insertion point of key in smap, which is a
	// string with consecutive 4-byte entries. Only the first len(key)
	// bytes from the start of the 4-byte entries will be considered.
	func search(smap, key string) int {
	n := len(key)
	return sort.Search(len(smap)>>2, func(i int) bool {
	return get(smap, i, n) >= key
	}) << 2
	}

	func index(smap, key string) int {
	i := search(smap, key)
	if smap[i:i+len(key)] != key {
	return -1
	}
	return i
	}

	func searchUint(imap []uint16, key uint16) int {
	return sort.Search(len(imap), func(i int) bool {
	return imap[i] >= key
	})
	}

	// fixCase reformats s to the same pattern of cases as pat.
	// If string s is malformed, pat is returned.
	func fixCase(pat, s string) string {
	if len(pat) != len(s) {
	return pat
	}
	var b []byte
	for i, r := range pat {
	c := s[i]
	if r <= 'Z' {
	if s[i] >= 'a' {
	c -= 'z' - 'Z'
	}
	if c > 'Z' \|\| c < 'A' {
	return pat
	}
	} else {
	if s[i] <= 'Z' {
	c += 'z' - 'Z'
	}
	if c > 'z' \|\| c < 'a' {
	return pat
	}
	}
	if b == nil {
	if s[i] == c {
	continue
	}
	b = make([]byte, len(pat))
	copy(b, s[:i])
	}
	b[i] = c
	}
	if b == nil {
	return s
	}
	return string(b)
	}

	type langID uint16

	// getLangID returns the langID of s if s is a canonical ID
	// or langUnknown if s is not a canonical langID.
	func getLangID(s string) langID {
	if len(s) == 2 {
	return getLangISO2(s)
	}
	return getLangISO3(s)
	}

	func getMappedID(index int) langID {
	m := mappedLang[index:]
	if m[3] >= 'a' {
	return getLangISO2(m[:1] + m[3:4])
	}
	i := mappedLangID[m[3]]
	if i < 0 {
	i = -(i + 1)
	// TODO: this code can be a locale.
	return getLangISO2(altTag[i:][:2])
	}
	return langID(i)
	}

	// normLang returns the langID of s, canonicalizing the language
	// according to BCP47 and CLDR rules.
	func normLang(s string) langID {
	s = getLangID(s).String()
	if len(s) < 2 \|\| len(s) > 3 {
	return unknownLang
	}
	if i := index(mappedLang, s); i != -1 {
	if len(s) == 3 \|\| mappedLang[i+2] == ' ' {
	return getMappedID(i)
	}
	}
	return getLangID(s)
	}

	// getLangISO2 returns the langID for the given 2-letter ISO language code
	// or unknownLang if this does not exist.
	func getLangISO2(s string) langID {
	if len(s) == 2 {
	s = fixCase("zz", s)
	if i := index(lang, s); i != -1 && lang[i+3] != 0 {
	return langID(i >> 2)
	}
	if i := index(mappedLang, s); i != -1 && mappedLang[i+2] == ' ' {
	return getMappedID(i)
	}
	}
	return unknownLang
	}

	// getLangISO3 returns the langID for the given 3-letter ISO language code
	// or unknownLang if this does not exist.
	func getLangISO3(s string) langID {
	s = fixCase("und", s)
	// first try to match canonical 3-letter entries
	for i := search(lang, s[:2]); lang[i:i+2] == s[:2]; i += 4 {
	if lang[i+3] == 0 && lang[i+2] == s[2] {
	return langID(i >> 2)
	}
	}
	if i := index(mappedLang, s); i != -1 {
	return getMappedID(i)
	}
	// Check for non-canonical uses of ISO3.
	for i := search(lang, s[:1]); lang[i] == s[0]; i += 4 {
	if lang[i+2:][:2] == s[1:3] {
	return langID(i >> 2)
	}
	}
	return unknownLang
	}

	// String returns the BCP47 representation of the langID.
	func (id langID) String() string {
	l := lang[id<<2:]
	if l[3] == 0 {
	return l[:3]
	}
	return l[:2]
	}

	// ISO3 returns the ISO 639-3 language code.
	func (id langID) iso3() string {
	l := lang[id<<2:]
	if l[3] == 0 {
	return l[:3]
	} else if l[2] == 0 {
	return get(mappedLang, int(l[3]), 3)
	}
	// This allocation will only happen for 3-letter ISO codes
	// that are non-canonical BCP47 language identifiers.
	return l[0:1] + l[2:4]
	}

	type regionID uint16

	// getRegionID returns the region id for s if s is a valid 2-letter region code
	// or unknownRegion.
	func getRegionID(s string) regionID {
	if len(s) == 3 {
	if s[0] >= 'A' {
	return getRegionISO3(s)
	}
	if i, err := strconv.ParseUint(s, 10, 10); err == nil {
	return getRegionM49(int(i))
	}
	}
	return getRegionISO2(s)
	}

	// getRegionISO2 returns the regionID for the given 2-letter ISO country code
	// or unknownRegion if this does not exist.
	func getRegionISO2(s string) regionID {
	if i := index(regionISO, fixCase("ZZ", s)); i != -1 {
	return regionID(i>>2) + isoRegionOffset
	}
	return unknownRegion
	}

	// getRegionISO3 returns the regionID for the given 3-letter ISO country code
	// or unknownRegion if this does not exist.
	func getRegionISO3(s string) regionID {
	s = fixCase("ZZZ", s)
	for i := search(regionISO, s[:1]); regionISO[i] == s[0]; i += 4 {
	if regionISO[i+2:][:2] == s[1:3] {
	return regionID(i>>2) + isoRegionOffset
	}
	}
	for i := 0; i < len(altRegionISO3); i += 3 {
	if altRegionISO3[i:i+3] == s {
	return regionID(altRegionIDs[i/3])
	}
	}
	return unknownRegion
	}

	func getRegionM49(n int) regionID {
	// These will mostly be group IDs, which are at the start of the list.
	// For other values this may be a bit slow, as there are over 300 entries.
	// TODO: group id is sorted!
	if n == 0 {
	return unknownRegion
	}
	for i, v := range m49 {
	if v == uint16(n) {
	return regionID(i)
	}
	}
	return unknownRegion
	}

	// String returns the BCP47 representation for the region.
	func (r regionID) String() string {
	if r < isoRegionOffset {
	return fmt.Sprintf("%03d", r.m49())
	}
	r -= isoRegionOffset
	return get(regionISO, int(r), 2)
	}

	// The use of this is uncommon.
	// Note: not all regionIDs have corresponding 3-letter ISO codes!
	func (r regionID) iso3() string {
	if r < isoRegionOffset {
	return ""
	}
	r -= isoRegionOffset
	reg := regionISO[r<<2:]
	switch reg[2] {
	case 0:
	return altRegionISO3[reg[3]:][:3]
	case ' ':
	return ""
	}
	return reg[0:1] + reg[2:4]
	}

	func (r regionID) m49() uint16 {
	return m49[r]
	}

	type scriptID uint8

	// getScriptID returns the script id for string s. It assumes that s
	// is of the format [A-Z][a-z]{3}.
	func getScriptID(idx, s string) scriptID {
	if i := index(idx, fixCase("Zzzz", s)); i != -1 {
	return scriptID(i >> 2)
	}
	return unknownScript
	}

	func (s scriptID) String() string {
	return get(script, int(s), 4)
	}

	type currencyID uint16

	func getCurrencyID(idx, s string) currencyID {
	if i := index(idx, fixCase("XXX", s)); i != -1 {
	return currencyID(i >> 2)
	}
	return unknownCurrency
	}

	func round(index string, c currencyID) int {
	return int(index[c<<2+3] >> 2)
	}

	func decimals(index string, c currencyID) int {
	return int(index[c<<2+3] & 0x03)
	}