src/pkg/unicode/maketables.go - go - Git at Google

 // Copyright 2009 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.

 // Unicode table generator.
 // Data read from the web.

 package main

 import (
 	"bufio"
 	"flag"
 	"fmt"
 	"http"
 	"log"
 	"os"
 	"sort"
 	"strconv"
 	"strings"
 	"regexp"
 	"unicode"
 )

 func main() {
 	flag.Parse()
 	loadChars() // always needed
 	printCategories()
 	printScriptOrProperty(false)
 	printScriptOrProperty(true)
 	printCases()
 }

 var dataURL = flag.String("data", "", "full URL for UnicodeData.txt; defaults to --url/UnicodeData.txt")
 var url = flag.String("url",
 	"http://www.unicode.org/Public/5.2.0/ucd/",
 	"URL of Unicode database directory")
 var tablelist = flag.String("tables",
 	"all",
 	"comma-separated list of which tables to generate; can be letter")
 var scriptlist = flag.String("scripts",
 	"all",
 	"comma-separated list of which script tables to generate")
 var proplist = flag.String("props",
 	"all",
 	"comma-separated list of which property tables to generate")
 var cases = flag.Bool("cases",
 	true,
 	"generate case tables")
 var test = flag.Bool("test",
 	false,
 	"test existing tables; can be used to compare web data with package data")

 var scriptRe = regexp.MustCompile(`([0-9A-F]+)(\.\.[0-9A-F]+)? *; ([A-Za-z_]+)`)
 var die = log.New(os.Stderr, nil, "", log.Lexit|log.Lshortfile)

 var category = map[string]bool{"letter": true} // Nd Lu etc. letter is a special case

 // UnicodeData.txt has form:
 //	0037;DIGIT SEVEN;Nd;0;EN;;7;7;7;N;;;;;
 //	007A;LATIN SMALL LETTER Z;Ll;0;L;;;;;N;;;005A;;005A
 // See http://www.unicode.org/Public/5.1.0/ucd/UCD.html for full explanation
 // The fields:
 const (
 	FCodePoint = iota
 	FName
 	FGeneralCategory
 	FCanonicalCombiningClass
 	FBidiClass
 	FDecompositionType
 	FDecompositionMapping
 	FNumericType
 	FNumericValue
 	FBidiMirrored
 	FUnicode1Name
 	FISOComment
 	FSimpleUppercaseMapping
 	FSimpleLowercaseMapping
 	FSimpleTitlecaseMapping
 	NumField

 	MaxChar = 0x10FFFF // anything above this shouldn't exist
 )

 var fieldName = []string{
 	"CodePoint",
 	"Name",
 	"GeneralCategory",
 	"CanonicalCombiningClass",
 	"BidiClass",
 	"DecompositionType",
 	"DecompositionMapping",
 	"NumericType",
 	"NumericValue",
 	"BidiMirrored",
 	"Unicode1Name",
 	"ISOComment",
 	"SimpleUppercaseMapping",
 	"SimpleLowercaseMapping",
 	"SimpleTitlecaseMapping",
 }

 // This contains only the properties we're interested in.
 type Char struct {
 	field     []string // debugging only; could be deleted if we take out char.dump()
 	codePoint uint32   // if zero, this index is not a valid code point.
 	category  string
 	upperCase int
 	lowerCase int
 	titleCase int
 }

 // Scripts.txt has form:
 //	A673          ; Cyrillic # Po       SLAVONIC ASTERISK
 //	A67C..A67D    ; Cyrillic # Mn   [2] COMBINING CYRILLIC KAVYKA..COMBINING CYRILLIC PAYEROK
 // See http://www.unicode.org/Public/5.1.0/ucd/UCD.html for full explanation

 type Script struct {
 	lo, hi uint32 // range of code points
 	script string
 }

 var chars = make([]Char, MaxChar+1)
 var scripts = make(map[string][]Script)
 var props = make(map[string][]Script) // a property looks like a script; can share the format

 var lastChar uint32 = 0

 // In UnicodeData.txt, some ranges are marked like this:
 //	3400;<CJK Ideograph Extension A, First>;Lo;0;L;;;;;N;;;;;
 //	4DB5;<CJK Ideograph Extension A, Last>;Lo;0;L;;;;;N;;;;;
 // parseCategory returns a state variable indicating the weirdness.
 type State int

 const (
 	SNormal State = iota // known to be zero for the type
 	SFirst
 	SLast
 	SMissing
 )

 func parseCategory(line string) (state State) {
 	field := strings.Split(line, ";", -1)
 	if len(field) != NumField {
 		die.Logf("%5s: %d fields (expected %d)\n", line, len(field), NumField)
 	}
 	point, err := strconv.Btoui64(field[FCodePoint], 16)
 	if err != nil {
 		die.Log("%.5s...:", err)
 	}
 	lastChar = uint32(point)
 	if point == 0 {
 		return // not interesting and we use 0 as unset
 	}
 	if point > MaxChar {
 		return
 	}
 	char := &chars[point]
 	char.field = field
 	if char.codePoint != 0 {
 		die.Logf("point U+%04x reused\n")
 	}
 	char.codePoint = lastChar
 	char.category = field[FGeneralCategory]
 	category[char.category] = true
 	switch char.category {
 	case "Nd":
 		// Decimal digit
 		_, err := strconv.Atoi(field[FNumericValue])
 		if err != nil {
 			die.Log("U+%04x: bad numeric field: %s", point, err)
 		}
 	case "Lu":
 		char.letter(field[FCodePoint], field[FSimpleLowercaseMapping], field[FSimpleTitlecaseMapping])
 	case "Ll":
 		char.letter(field[FSimpleUppercaseMapping], field[FCodePoint], field[FSimpleTitlecaseMapping])
 	case "Lt":
 		char.letter(field[FSimpleUppercaseMapping], field[FSimpleLowercaseMapping], field[FCodePoint])
 	case "Lm", "Lo":
 		char.letter(field[FSimpleUppercaseMapping], field[FSimpleLowercaseMapping], field[FSimpleTitlecaseMapping])
 	}
 	switch {
 	case strings.Index(field[FName], ", First>") > 0:
 		state = SFirst
 	case strings.Index(field[FName], ", Last>") > 0:
 		state = SLast
 	}
 	return
 }

 func (char *Char) dump(s string) {
 	fmt.Print(s, " ")
 	for i := 0; i < len(char.field); i++ {
 		fmt.Printf("%s:%q ", fieldName[i], char.field[i])
 	}
 	fmt.Print("\n")
 }

 func (char *Char) letter(u, l, t string) {
 	char.upperCase = char.letterValue(u, "U")
 	char.lowerCase = char.letterValue(l, "L")
 	char.titleCase = char.letterValue(t, "T")
 }

 func (char *Char) letterValue(s string, cas string) int {
 	if s == "" {
 		return 0
 	}
 	v, err := strconv.Btoui64(s, 16)
 	if err != nil {
 		char.dump(cas)
 		die.Logf("U+%04x: bad letter(%s): %s", char.codePoint, s, err)
 	}
 	return int(v)
 }

 func allCategories() []string {
 	a := make([]string, len(category))
 	i := 0
 	for k := range category {
 		a[i] = k
 		i++
 	}
 	return a
 }

 func all(scripts map[string][]Script) []string {
 	a := make([]string, len(scripts))
 	i := 0
 	for k := range scripts {
 		a[i] = k
 		i++
 	}
 	return a
 }

 // Extract the version number from the URL
 func version() string {
 	// Break on slashes and look for the first numeric field
 	fields := strings.Split(*url, "/", 0)
 	for _, f := range fields {
 		if len(f) > 0 && '0' <= f[0] && f[0] <= '9' {
 			return f
 		}
 	}
 	die.Log("unknown version")
 	return "Unknown"
 }

 func letterOp(code int) bool {
 	switch chars[code].category {
 	case "Lu", "Ll", "Lt", "Lm", "Lo":
 		return true
 	}
 	return false
 }

 func loadChars() {
 	if *dataURL == "" {
 		flag.Set("data", *url+"UnicodeData.txt")
 	}
 	resp, _, err := http.Get(*dataURL)
 	if err != nil {
 		die.Log(err)
 	}
 	if resp.StatusCode != 200 {
 		die.Log("bad GET status for UnicodeData.txt", resp.Status)
 	}
 	input := bufio.NewReader(resp.Body)
 	var first uint32 = 0
 	for {
 		line, err := input.ReadString('\n')
 		if err != nil {
 			if err == os.EOF {
 				break
 			}
 			die.Log(err)
 		}
 		switch parseCategory(line[0 : len(line)-1]) {
 		case SNormal:
 			if first != 0 {
 				die.Logf("bad state normal at U+%04X", lastChar)
 			}
 		case SFirst:
 			if first != 0 {
 				die.Logf("bad state first at U+%04X", lastChar)
 			}
 			first = lastChar
 		case SLast:
 			if first == 0 {
 				die.Logf("bad state last at U+%04X", lastChar)
 			}
 			for i := first + 1; i <= lastChar; i++ {
 				chars[i] = chars[first]
 				chars[i].codePoint = i
 			}
 			first = 0
 		}
 	}
 	resp.Body.Close()
 }

 func printCategories() {
 	if *tablelist == "" {
 		return
 	}
 	// Find out which categories to dump
 	list := strings.Split(*tablelist, ",", 0)
 	if *tablelist == "all" {
 		list = allCategories()
 	}
 	if *test {
 		fullCategoryTest(list)
 		return
 	}
 	fmt.Printf(
 		"// Generated by running\n"+
 			"//	maketables --tables=%s --data=%s\n"+
 			"// DO NOT EDIT\n\n"+
 			"package unicode\n\n",
 		*tablelist,
 		*dataURL)

 	fmt.Println("// Version is the Unicode edition from which the tables are derived.")
 	fmt.Printf("const Version = %q\n\n", version())

 	if *tablelist == "all" {
 		fmt.Println("// Categories is the set of Unicode data tables.")
 		fmt.Println("var Categories = map[string] []Range {")
 		for k, _ := range category {
 			fmt.Printf("\t%q: %s,\n", k, k)
 		}
 		fmt.Printf("}\n\n")
 	}

 	decl := make(sort.StringArray, len(list))
 	ndecl := 0
 	for _, name := range list {
 		if _, ok := category[name]; !ok {
 			die.Log("unknown category", name)
 		}
 		// We generate an UpperCase name to serve as concise documentation and an _UnderScored
 		// name to store the data.  This stops godoc dumping all the tables but keeps them
 		// available to clients.
 		// Cases deserving special comments
 		varDecl := ""
 		switch name {
 		case "letter":
 			varDecl = "\tLetter = letter;	// Letter is the set of Unicode letters.\n"
 		case "Nd":
 			varDecl = "\tDigit = _Nd;	// Digit is the set of Unicode characters with the \"decimal digit\" property.\n"
 		case "Lu":
 			varDecl = "\tUpper = _Lu;	// Upper is the set of Unicode upper case letters.\n"
 		case "Ll":
 			varDecl = "\tLower = _Ll;	// Lower is the set of Unicode lower case letters.\n"
 		case "Lt":
 			varDecl = "\tTitle = _Lt;	// Title is the set of Unicode title case letters.\n"
 		}
 		if name != "letter" {
 			varDecl += fmt.Sprintf(
 				"\t%s = _%s;	// %s is the set of Unicode characters in category %s.\n",
 				name, name, name, name)
 		}
 		decl[ndecl] = varDecl
 		ndecl++
 		if name == "letter" { // special case
 			dumpRange(
 				"var letter = []Range {\n",
 				letterOp)
 			continue
 		}
 		dumpRange(
 			fmt.Sprintf("var _%s = []Range {\n", name),
 			func(code int) bool { return chars[code].category == name })
 	}
 	decl.Sort()
 	fmt.Println("var (")
 	for _, d := range decl {
 		fmt.Print(d)
 	}
 	fmt.Println(")\n")
 }

 type Op func(code int) bool

 const format = "\tRange{0x%04x, 0x%04x, %d},\n"

 func dumpRange(header string, inCategory Op) {
 	fmt.Print(header)
 	next := 0
 	// one Range for each iteration
 	for {
 		// look for start of range
 		for next < len(chars) && !inCategory(next) {
 			next++
 		}
 		if next >= len(chars) {
 			// no characters remain
 			break
 		}

 		// start of range
 		lo := next
 		hi := next
 		stride := 1
 		// accept lo
 		next++
 		// look for another character to set the stride
 		for next < len(chars) && !inCategory(next) {
 			next++
 		}
 		if next >= len(chars) {
 			// no more characters
 			fmt.Printf(format, lo, hi, stride)
 			break
 		}
 		// set stride
 		stride = next - lo
 		// check for length of run. next points to first jump in stride
 		for i := next; i < len(chars); i++ {
 			if inCategory(i) == (((i - lo) % stride) == 0) {
 				// accept
 				if inCategory(i) {
 					hi = i
 				}
 			} else {
 				// no more characters in this run
 				break
 			}
 		}
 		fmt.Printf(format, lo, hi, stride)
 		// next range: start looking where this range ends
 		next = hi + 1
 	}
 	fmt.Print("}\n\n")
 }

 func fullCategoryTest(list []string) {
 	for _, name := range list {
 		if _, ok := category[name]; !ok {
 			die.Log("unknown category", name)
 		}
 		r, ok := unicode.Categories[name]
 		if !ok {
 			die.Log("unknown table", name)
 		}
 		if name == "letter" {
 			verifyRange(name, letterOp, r)
 		} else {
 			verifyRange(
 				name,
 				func(code int) bool { return chars[code].category == name },
 				r)
 		}
 	}
 }

 func verifyRange(name string, inCategory Op, table []unicode.Range) {
 	for i := range chars {
 		web := inCategory(i)
 		pkg := unicode.Is(table, i)
 		if web != pkg {
 			fmt.Fprintf(os.Stderr, "%s: U+%04X: web=%t pkg=%t\n", name, i, web, pkg)
 		}
 	}
 }

 func parseScript(line string, scripts map[string][]Script) {
 	comment := strings.Index(line, "#")
 	if comment >= 0 {
 		line = line[0:comment]
 	}
 	line = strings.TrimSpace(line)
 	if len(line) == 0 {
 		return
 	}
 	field := strings.Split(line, ";", -1)
 	if len(field) != 2 {
 		die.Logf("%s: %d fields (expected 2)\n", line, len(field))
 	}
 	matches := scriptRe.MatchStrings(line)
 	if len(matches) != 4 {
 		die.Logf("%s: %d matches (expected 3)\n", line, len(matches))
 	}
 	lo, err := strconv.Btoui64(matches[1], 16)
 	if err != nil {
 		die.Log("%.5s...:", err)
 	}
 	hi := lo
 	if len(matches[2]) > 2 { // ignore leading ..
 		hi, err = strconv.Btoui64(matches[2][2:], 16)
 		if err != nil {
 			die.Log("%.5s...:", err)
 		}
 	}
 	name := matches[3]
 	s, ok := scripts[name]
 	if !ok || len(s) == cap(s) {
 		ns := make([]Script, len(s), len(s)+100)
 		for i, sc := range s {
 			ns[i] = sc
 		}
 		s = ns
 	}
 	s = s[0 : len(s)+1]
 	s[len(s)-1] = Script{uint32(lo), uint32(hi), name}
 	scripts[name] = s
 }

 // The script tables have a lot of adjacent elements. Fold them together.
 func foldAdjacent(r []Script) []unicode.Range {
 	s := make([]unicode.Range, 0, len(r))
 	j := 0
 	for i := 0; i < len(r); i++ {
 		if j > 0 && int(r[i].lo) == s[j-1].Hi+1 {
 			s[j-1].Hi = int(r[i].hi)
 		} else {
 			s = s[0 : j+1]
 			s[j] = unicode.Range{int(r[i].lo), int(r[i].hi), 1}
 			j++
 		}
 	}
 	return s
 }

 func fullScriptTest(list []string, installed map[string][]unicode.Range, scripts map[string][]Script) {
 	for _, name := range list {
 		if _, ok := scripts[name]; !ok {
 			die.Log("unknown script", name)
 		}
 		_, ok := installed[name]
 		if !ok {
 			die.Log("unknown table", name)
 		}
 		for _, script := range scripts[name] {
 			for r := script.lo; r <= script.hi; r++ {
 				if !unicode.Is(installed[name], int(r)) {
 					fmt.Fprintf(os.Stderr, "U+%04X: not in script %s\n", r, name)
 				}
 			}
 		}
 	}
 }

 // PropList.txt has the same format as Scripts.txt so we can share its parser.
 func printScriptOrProperty(doProps bool) {
 	flag := "scripts"
 	flaglist := *scriptlist
 	file := "Scripts.txt"
 	table := scripts
 	installed := unicode.Scripts
 	if doProps {
 		flag = "props"
 		flaglist = *proplist
 		file = "PropList.txt"
 		table = props
 		installed = unicode.Properties
 	}
 	if flaglist == "" {
 		return
 	}
 	var err os.Error
 	resp, _, err := http.Get(*url + file)
 	if err != nil {
 		die.Log(err)
 	}
 	if resp.StatusCode != 200 {
 		die.Log("bad GET status for ", file, ":", resp.Status)
 	}
 	input := bufio.NewReader(resp.Body)
 	for {
 		line, err := input.ReadString('\n')
 		if err != nil {
 			if err == os.EOF {
 				break
 			}
 			die.Log(err)
 		}
 		parseScript(line[0:len(line)-1], table)
 	}
 	resp.Body.Close()

 	// Find out which scripts to dump
 	list := strings.Split(flaglist, ",", 0)
 	if flaglist == "all" {
 		list = all(table)
 	}
 	if *test {
 		fullScriptTest(list, installed, table)
 		return
 	}

 	fmt.Printf(
 		"// Generated by running\n"+
 			"//	maketables --%s=%s --url=%s\n"+
 			"// DO NOT EDIT\n\n",
 		flag,
 		flaglist,
 		*url)
 	if flaglist == "all" {
 		if doProps {
 			fmt.Println("// Properties is the set of Unicode property tables.")
 			fmt.Println("var Properties = map[string] []Range {")
 		} else {
 			fmt.Println("// Scripts is the set of Unicode script tables.")
 			fmt.Println("var Scripts = map[string] []Range {")
 		}
 		for k, _ := range table {
 			fmt.Printf("\t%q: %s,\n", k, k)
 		}
 		fmt.Printf("}\n\n")
 	}

 	decl := make(sort.StringArray, len(list))
 	ndecl := 0
 	for _, name := range list {
 		if doProps {
 			decl[ndecl] = fmt.Sprintf(
 				"\t%s = _%s;\t// %s is the set of Unicode characters with property %s.\n",
 				name, name, name, name)
 		} else {
 			decl[ndecl] = fmt.Sprintf(
 				"\t%s = _%s;\t// %s is the set of Unicode characters in script %s.\n",
 				name, name, name, name)
 		}
 		ndecl++
 		fmt.Printf("var _%s = []Range {\n", name)
 		ranges := foldAdjacent(table[name])
 		for _, s := range ranges {
 			fmt.Printf(format, s.Lo, s.Hi, s.Stride)
 		}
 		fmt.Printf("}\n\n")
 	}
 	decl.Sort()
 	fmt.Println("var (")
 	for _, d := range decl {
 		fmt.Print(d)
 	}
 	fmt.Println(")\n")
 }

 const (
 	CaseUpper = 1 << iota
 	CaseLower
 	CaseTitle
 	CaseNone    = 0  // must be zero
 	CaseMissing = -1 // character not present; not a valid case state
 )

 type caseState struct {
 	point        int
 	_case        int
 	deltaToUpper int
 	deltaToLower int
 	deltaToTitle int
 }

 // Is d a continuation of the state of c?
 func (c *caseState) adjacent(d *caseState) bool {
 	if d.point < c.point {
 		c, d = d, c
 	}
 	switch {
 	case d.point != c.point+1: // code points not adjacent (shouldn't happen)
 		return false
 	case d._case != c._case: // different cases
 		return c.upperLowerAdjacent(d)
 	case c._case == CaseNone:
 		return false
 	case c._case == CaseMissing:
 		return false
 	case d.deltaToUpper != c.deltaToUpper:
 		return false
 	case d.deltaToLower != c.deltaToLower:
 		return false
 	case d.deltaToTitle != c.deltaToTitle:
 		return false
 	}
 	return true
 }

 // Is d the same as c, but opposite in upper/lower case? this would make it
 // an element of an UpperLower sequence.
 func (c *caseState) upperLowerAdjacent(d *caseState) bool {
 	// check they're a matched case pair.  we know they have adjacent values
 	switch {
 	case c._case == CaseUpper && d._case != CaseLower:
 		return false
 	case c._case == CaseLower && d._case != CaseUpper:
 		return false
 	}
 	// matched pair (at least in upper/lower).  make the order Upper Lower
 	if c._case == CaseLower {
 		c, d = d, c
 	}
 	// for an Upper Lower sequence the deltas have to be in order
 	//	c: 0 1 0
 	//	d: -1 0 -1
 	switch {
 	case c.deltaToUpper != 0:
 		return false
 	case c.deltaToLower != 1:
 		return false
 	case c.deltaToTitle != 0:
 		return false
 	case d.deltaToUpper != -1:
 		return false
 	case d.deltaToLower != 0:
 		return false
 	case d.deltaToTitle != -1:
 		return false
 	}
 	return true
 }

 // Does this character start an UpperLower sequence?
 func (c *caseState) isUpperLower() bool {
 	// for an Upper Lower sequence the deltas have to be in order
 	//	c: 0 1 0
 	switch {
 	case c.deltaToUpper != 0:
 		return false
 	case c.deltaToLower != 1:
 		return false
 	case c.deltaToTitle != 0:
 		return false
 	}
 	return true
 }

 // Does this character start a LowerUpper sequence?
 func (c *caseState) isLowerUpper() bool {
 	// for an Upper Lower sequence the deltas have to be in order
 	//	c: -1 0 -1
 	switch {
 	case c.deltaToUpper != -1:
 		return false
 	case c.deltaToLower != 0:
 		return false
 	case c.deltaToTitle != -1:
 		return false
 	}
 	return true
 }

 func getCaseState(i int) (c *caseState) {
 	c = &caseState{point: i, _case: CaseNone}
 	ch := &chars[i]
 	switch int(ch.codePoint) {
 	case 0:
 		c._case = CaseMissing // Will get NUL wrong but that doesn't matter
 		return
 	case ch.upperCase:
 		c._case = CaseUpper
 	case ch.lowerCase:
 		c._case = CaseLower
 	case ch.titleCase:
 		c._case = CaseTitle
 	}
 	if ch.upperCase != 0 {
 		c.deltaToUpper = ch.upperCase - i
 	}
 	if ch.lowerCase != 0 {
 		c.deltaToLower = ch.lowerCase - i
 	}
 	if ch.titleCase != 0 {
 		c.deltaToTitle = ch.titleCase - i
 	}
 	return
 }

 func printCases() {
 	if !*cases {
 		return
 	}
 	if *test {
 		fullCaseTest()
 		return
 	}
 	fmt.Printf(
 		"// Generated by running\n"+
 			"//	maketables --data=%s\n"+
 			"// DO NOT EDIT\n\n"+
 			"// CaseRanges is the table describing case mappings for all letters with\n"+
 			"// non-self mappings.\n"+
 			"var CaseRanges = _CaseRanges\n"+
 			"var _CaseRanges = []CaseRange {\n",
 		*dataURL)

 	var startState *caseState    // the start of a run; nil for not active
 	var prevState = &caseState{} // the state of the previous character
 	for i := range chars {
 		state := getCaseState(i)
 		if state.adjacent(prevState) {
 			prevState = state
 			continue
 		}
 		// end of run (possibly)
 		printCaseRange(startState, prevState)
 		startState = nil
 		if state._case != CaseMissing && state._case != CaseNone {
 			startState = state
 		}
 		prevState = state
 	}
 	fmt.Printf("}\n")
 }

 func printCaseRange(lo, hi *caseState) {
 	if lo == nil {
 		return
 	}
 	if lo.deltaToUpper == 0 && lo.deltaToLower == 0 && lo.deltaToTitle == 0 {
 		// character represents itself in all cases - no need to mention it
 		return
 	}
 	switch {
 	case hi.point > lo.point && lo.isUpperLower():
 		fmt.Printf("\tCaseRange{0x%04X, 0x%04X, d{UpperLower, UpperLower, UpperLower}},\n",
 			lo.point, hi.point)
 	case hi.point > lo.point && lo.isLowerUpper():
 		die.Log("LowerUpper sequence: should not happen: U+%04X.  If it's real, need to fix To()", lo.point)
 		fmt.Printf("\tCaseRange{0x%04X, 0x%04X, d{LowerUpper, LowerUpper, LowerUpper}},\n",
 			lo.point, hi.point)
 	default:
 		fmt.Printf("\tCaseRange{0x%04X, 0x%04X, d{%d, %d, %d}},\n",
 			lo.point, hi.point,
 			lo.deltaToUpper, lo.deltaToLower, lo.deltaToTitle)
 	}
 }

 // If the cased value in the Char is 0, it means use the rune itself.
 func caseIt(rune, cased int) int {
 	if cased == 0 {
 		return rune
 	}
 	return cased
 }

 func fullCaseTest() {
 	for i, c := range chars {
 		lower := unicode.ToLower(i)
 		want := caseIt(i, c.lowerCase)
 		if lower != want {
 			fmt.Fprintf(os.Stderr, "lower U+%04X should be U+%04X is U+%04X\n", i, want, lower)
 		}
 		upper := unicode.ToUpper(i)
 		want = caseIt(i, c.upperCase)
 		if upper != want {
 			fmt.Fprintf(os.Stderr, "upper U+%04X should be U+%04X is U+%04X\n", i, want, upper)
 		}
 		title := unicode.ToTitle(i)
 		want = caseIt(i, c.titleCase)
 		if title != want {
 			fmt.Fprintf(os.Stderr, "title U+%04X should be U+%04X is U+%04X\n", i, want, title)
 		}
 	}
 }
	// Copyright 2009 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.

	// Unicode table generator.
	// Data read from the web.

	package main

	import (
	"bufio"
	"flag"
	"fmt"
	"http"
	"log"
	"os"
	"sort"
	"strconv"
	"strings"
	"regexp"
	"unicode"
	)

	func main() {
	flag.Parse()
	loadChars() // always needed
	printCategories()
	printScriptOrProperty(false)
	printScriptOrProperty(true)
	printCases()
	}

	var dataURL = flag.String("data", "", "full URL for UnicodeData.txt; defaults to --url/UnicodeData.txt")
	var url = flag.String("url",
	"http://www.unicode.org/Public/5.2.0/ucd/",
	"URL of Unicode database directory")
	var tablelist = flag.String("tables",
	"all",
	"comma-separated list of which tables to generate; can be letter")
	var scriptlist = flag.String("scripts",
	"all",
	"comma-separated list of which script tables to generate")
	var proplist = flag.String("props",
	"all",
	"comma-separated list of which property tables to generate")
	var cases = flag.Bool("cases",
	true,
	"generate case tables")
	var test = flag.Bool("test",
	false,
	"test existing tables; can be used to compare web data with package data")

	var scriptRe = regexp.MustCompile(`([0-9A-F]+)(\.\.[0-9A-F]+)? *; ([A-Za-z_]+)`)
	var die = log.New(os.Stderr, nil, "", log.Lexit\|log.Lshortfile)

	var category = map[string]bool{"letter": true} // Nd Lu etc. letter is a special case

	// UnicodeData.txt has form:
	// 0037;DIGIT SEVEN;Nd;0;EN;;7;7;7;N;;;;;
	// 007A;LATIN SMALL LETTER Z;Ll;0;L;;;;;N;;;005A;;005A
	// See http://www.unicode.org/Public/5.1.0/ucd/UCD.html for full explanation
	// The fields:
	const (
	FCodePoint = iota
	FName
	FGeneralCategory
	FCanonicalCombiningClass
	FBidiClass
	FDecompositionType
	FDecompositionMapping
	FNumericType
	FNumericValue
	FBidiMirrored
	FUnicode1Name
	FISOComment
	FSimpleUppercaseMapping
	FSimpleLowercaseMapping
	FSimpleTitlecaseMapping
	NumField

	MaxChar = 0x10FFFF // anything above this shouldn't exist
	)

	var fieldName = []string{
	"CodePoint",
	"Name",
	"GeneralCategory",
	"CanonicalCombiningClass",
	"BidiClass",
	"DecompositionType",
	"DecompositionMapping",
	"NumericType",
	"NumericValue",
	"BidiMirrored",
	"Unicode1Name",
	"ISOComment",
	"SimpleUppercaseMapping",
	"SimpleLowercaseMapping",
	"SimpleTitlecaseMapping",
	}

	// This contains only the properties we're interested in.
	type Char struct {
	field []string // debugging only; could be deleted if we take out char.dump()
	codePoint uint32 // if zero, this index is not a valid code point.
	category string
	upperCase int
	lowerCase int
	titleCase int
	}

	// Scripts.txt has form:
	// A673 ; Cyrillic # Po SLAVONIC ASTERISK
	// A67C..A67D ; Cyrillic # Mn [2] COMBINING CYRILLIC KAVYKA..COMBINING CYRILLIC PAYEROK
	// See http://www.unicode.org/Public/5.1.0/ucd/UCD.html for full explanation

	type Script struct {
	lo, hi uint32 // range of code points
	script string
	}

	var chars = make([]Char, MaxChar+1)
	var scripts = make(map[string][]Script)
	var props = make(map[string][]Script) // a property looks like a script; can share the format

	var lastChar uint32 = 0

	// In UnicodeData.txt, some ranges are marked like this:
	// 3400;<CJK Ideograph Extension A, First>;Lo;0;L;;;;;N;;;;;
	// 4DB5;<CJK Ideograph Extension A, Last>;Lo;0;L;;;;;N;;;;;
	// parseCategory returns a state variable indicating the weirdness.
	type State int

	const (
	SNormal State = iota // known to be zero for the type
	SFirst
	SLast
	SMissing
	)

	func parseCategory(line string) (state State) {
	field := strings.Split(line, ";", -1)
	if len(field) != NumField {
	die.Logf("%5s: %d fields (expected %d)\n", line, len(field), NumField)
	}
	point, err := strconv.Btoui64(field[FCodePoint], 16)
	if err != nil {
	die.Log("%.5s...:", err)
	}
	lastChar = uint32(point)
	if point == 0 {
	return // not interesting and we use 0 as unset
	}
	if point > MaxChar {
	return
	}
	char := &chars[point]
	char.field = field
	if char.codePoint != 0 {
	die.Logf("point U+%04x reused\n")
	}
	char.codePoint = lastChar
	char.category = field[FGeneralCategory]
	category[char.category] = true
	switch char.category {
	case "Nd":
	// Decimal digit
	_, err := strconv.Atoi(field[FNumericValue])
	if err != nil {
	die.Log("U+%04x: bad numeric field: %s", point, err)
	}
	case "Lu":
	char.letter(field[FCodePoint], field[FSimpleLowercaseMapping], field[FSimpleTitlecaseMapping])
	case "Ll":
	char.letter(field[FSimpleUppercaseMapping], field[FCodePoint], field[FSimpleTitlecaseMapping])
	case "Lt":
	char.letter(field[FSimpleUppercaseMapping], field[FSimpleLowercaseMapping], field[FCodePoint])
	case "Lm", "Lo":
	char.letter(field[FSimpleUppercaseMapping], field[FSimpleLowercaseMapping], field[FSimpleTitlecaseMapping])
	}
	switch {
	case strings.Index(field[FName], ", First>") > 0:
	state = SFirst
	case strings.Index(field[FName], ", Last>") > 0:
	state = SLast
	}
	return
	}

	func (char *Char) dump(s string) {
	fmt.Print(s, " ")
	for i := 0; i < len(char.field); i++ {
	fmt.Printf("%s:%q ", fieldName[i], char.field[i])
	}
	fmt.Print("\n")
	}

	func (char *Char) letter(u, l, t string) {
	char.upperCase = char.letterValue(u, "U")
	char.lowerCase = char.letterValue(l, "L")
	char.titleCase = char.letterValue(t, "T")
	}

	func (char *Char) letterValue(s string, cas string) int {
	if s == "" {
	return 0
	}
	v, err := strconv.Btoui64(s, 16)
	if err != nil {
	char.dump(cas)
	die.Logf("U+%04x: bad letter(%s): %s", char.codePoint, s, err)
	}
	return int(v)
	}

	func allCategories() []string {
	a := make([]string, len(category))
	i := 0
	for k := range category {
	a[i] = k
	i++
	}
	return a
	}

	func all(scripts map[string][]Script) []string {
	a := make([]string, len(scripts))
	i := 0
	for k := range scripts {
	a[i] = k
	i++
	}
	return a
	}

	// Extract the version number from the URL
	func version() string {
	// Break on slashes and look for the first numeric field
	fields := strings.Split(*url, "/", 0)
	for _, f := range fields {
	if len(f) > 0 && '0' <= f[0] && f[0] <= '9' {
	return f
	}
	}
	die.Log("unknown version")
	return "Unknown"
	}

	func letterOp(code int) bool {
	switch chars[code].category {
	case "Lu", "Ll", "Lt", "Lm", "Lo":
	return true
	}
	return false
	}

	func loadChars() {
	if *dataURL == "" {
	flag.Set("data", *url+"UnicodeData.txt")
	}
	resp, _, err := http.Get(*dataURL)
	if err != nil {
	die.Log(err)
	}
	if resp.StatusCode != 200 {
	die.Log("bad GET status for UnicodeData.txt", resp.Status)
	}
	input := bufio.NewReader(resp.Body)
	var first uint32 = 0
	for {
	line, err := input.ReadString('\n')
	if err != nil {
	if err == os.EOF {
	break
	}
	die.Log(err)
	}
	switch parseCategory(line[0 : len(line)-1]) {
	case SNormal:
	if first != 0 {
	die.Logf("bad state normal at U+%04X", lastChar)
	}
	case SFirst:
	if first != 0 {
	die.Logf("bad state first at U+%04X", lastChar)
	}
	first = lastChar
	case SLast:
	if first == 0 {
	die.Logf("bad state last at U+%04X", lastChar)
	}
	for i := first + 1; i <= lastChar; i++ {
	chars[i] = chars[first]
	chars[i].codePoint = i
	}
	first = 0
	}
	}
	resp.Body.Close()
	}

	func printCategories() {
	if *tablelist == "" {
	return
	}
	// Find out which categories to dump
	list := strings.Split(*tablelist, ",", 0)
	if *tablelist == "all" {
	list = allCategories()
	}
	if *test {
	fullCategoryTest(list)
	return
	}
	fmt.Printf(
	"// Generated by running\n"+
	"// maketables --tables=%s --data=%s\n"+
	"// DO NOT EDIT\n\n"+
	"package unicode\n\n",
	*tablelist,
	*dataURL)

	fmt.Println("// Version is the Unicode edition from which the tables are derived.")
	fmt.Printf("const Version = %q\n\n", version())

	if *tablelist == "all" {
	fmt.Println("// Categories is the set of Unicode data tables.")
	fmt.Println("var Categories = map[string] []Range {")
	for k, _ := range category {
	fmt.Printf("\t%q: %s,\n", k, k)
	}
	fmt.Printf("}\n\n")
	}

	decl := make(sort.StringArray, len(list))
	ndecl := 0
	for _, name := range list {
	if _, ok := category[name]; !ok {
	die.Log("unknown category", name)
	}
	// We generate an UpperCase name to serve as concise documentation and an _UnderScored
	// name to store the data. This stops godoc dumping all the tables but keeps them
	// available to clients.
	// Cases deserving special comments
	varDecl := ""
	switch name {
	case "letter":
	varDecl = "\tLetter = letter; // Letter is the set of Unicode letters.\n"
	case "Nd":
	varDecl = "\tDigit = _Nd; // Digit is the set of Unicode characters with the \"decimal digit\" property.\n"
	case "Lu":
	varDecl = "\tUpper = _Lu; // Upper is the set of Unicode upper case letters.\n"
	case "Ll":
	varDecl = "\tLower = _Ll; // Lower is the set of Unicode lower case letters.\n"
	case "Lt":
	varDecl = "\tTitle = _Lt; // Title is the set of Unicode title case letters.\n"
	}
	if name != "letter" {
	varDecl += fmt.Sprintf(
	"\t%s = _%s; // %s is the set of Unicode characters in category %s.\n",
	name, name, name, name)
	}
	decl[ndecl] = varDecl
	ndecl++
	if name == "letter" { // special case
	dumpRange(
	"var letter = []Range {\n",
	letterOp)
	continue
	}
	dumpRange(
	fmt.Sprintf("var _%s = []Range {\n", name),
	func(code int) bool { return chars[code].category == name })
	}
	decl.Sort()
	fmt.Println("var (")
	for _, d := range decl {
	fmt.Print(d)
	}
	fmt.Println(")\n")
	}

	type Op func(code int) bool

	const format = "\tRange{0x%04x, 0x%04x, %d},\n"

	func dumpRange(header string, inCategory Op) {
	fmt.Print(header)
	next := 0
	// one Range for each iteration
	for {
	// look for start of range
	for next < len(chars) && !inCategory(next) {
	next++
	}
	if next >= len(chars) {
	// no characters remain
	break
	}

	// start of range
	lo := next
	hi := next
	stride := 1
	// accept lo
	next++
	// look for another character to set the stride
	for next < len(chars) && !inCategory(next) {
	next++
	}
	if next >= len(chars) {
	// no more characters
	fmt.Printf(format, lo, hi, stride)
	break
	}
	// set stride
	stride = next - lo
	// check for length of run. next points to first jump in stride
	for i := next; i < len(chars); i++ {
	if inCategory(i) == (((i - lo) % stride) == 0) {
	// accept
	if inCategory(i) {
	hi = i
	}
	} else {
	// no more characters in this run
	break
	}
	}
	fmt.Printf(format, lo, hi, stride)
	// next range: start looking where this range ends
	next = hi + 1
	}
	fmt.Print("}\n\n")
	}

	func fullCategoryTest(list []string) {
	for _, name := range list {
	if _, ok := category[name]; !ok {
	die.Log("unknown category", name)
	}
	r, ok := unicode.Categories[name]
	if !ok {
	die.Log("unknown table", name)
	}
	if name == "letter" {
	verifyRange(name, letterOp, r)
	} else {
	verifyRange(
	name,
	func(code int) bool { return chars[code].category == name },
	r)
	}
	}
	}

	func verifyRange(name string, inCategory Op, table []unicode.Range) {
	for i := range chars {
	web := inCategory(i)
	pkg := unicode.Is(table, i)
	if web != pkg {
	fmt.Fprintf(os.Stderr, "%s: U+%04X: web=%t pkg=%t\n", name, i, web, pkg)
	}
	}
	}

	func parseScript(line string, scripts map[string][]Script) {
	comment := strings.Index(line, "#")
	if comment >= 0 {
	line = line[0:comment]
	}
	line = strings.TrimSpace(line)
	if len(line) == 0 {
	return
	}
	field := strings.Split(line, ";", -1)
	if len(field) != 2 {
	die.Logf("%s: %d fields (expected 2)\n", line, len(field))
	}
	matches := scriptRe.MatchStrings(line)
	if len(matches) != 4 {
	die.Logf("%s: %d matches (expected 3)\n", line, len(matches))
	}
	lo, err := strconv.Btoui64(matches[1], 16)
	if err != nil {
	die.Log("%.5s...:", err)
	}
	hi := lo
	if len(matches[2]) > 2 { // ignore leading ..
	hi, err = strconv.Btoui64(matches[2][2:], 16)
	if err != nil {
	die.Log("%.5s...:", err)
	}
	}
	name := matches[3]
	s, ok := scripts[name]
	if !ok \|\| len(s) == cap(s) {
	ns := make([]Script, len(s), len(s)+100)
	for i, sc := range s {
	ns[i] = sc
	}
	s = ns
	}
	s = s[0 : len(s)+1]
	s[len(s)-1] = Script{uint32(lo), uint32(hi), name}
	scripts[name] = s
	}

	// The script tables have a lot of adjacent elements. Fold them together.
	func foldAdjacent(r []Script) []unicode.Range {
	s := make([]unicode.Range, 0, len(r))
	j := 0
	for i := 0; i < len(r); i++ {
	if j > 0 && int(r[i].lo) == s[j-1].Hi+1 {
	s[j-1].Hi = int(r[i].hi)
	} else {
	s = s[0 : j+1]
	s[j] = unicode.Range{int(r[i].lo), int(r[i].hi), 1}
	j++
	}
	}
	return s
	}

	func fullScriptTest(list []string, installed map[string][]unicode.Range, scripts map[string][]Script) {
	for _, name := range list {
	if _, ok := scripts[name]; !ok {
	die.Log("unknown script", name)
	}
	_, ok := installed[name]
	if !ok {
	die.Log("unknown table", name)
	}
	for _, script := range scripts[name] {
	for r := script.lo; r <= script.hi; r++ {
	if !unicode.Is(installed[name], int(r)) {
	fmt.Fprintf(os.Stderr, "U+%04X: not in script %s\n", r, name)
	}
	}
	}
	}
	}

	// PropList.txt has the same format as Scripts.txt so we can share its parser.
	func printScriptOrProperty(doProps bool) {
	flag := "scripts"
	flaglist := *scriptlist
	file := "Scripts.txt"
	table := scripts
	installed := unicode.Scripts
	if doProps {
	flag = "props"
	flaglist = *proplist
	file = "PropList.txt"
	table = props
	installed = unicode.Properties
	}
	if flaglist == "" {
	return
	}
	var err os.Error
	resp, _, err := http.Get(*url + file)
	if err != nil {
	die.Log(err)
	}
	if resp.StatusCode != 200 {
	die.Log("bad GET status for ", file, ":", resp.Status)
	}
	input := bufio.NewReader(resp.Body)
	for {
	line, err := input.ReadString('\n')
	if err != nil {
	if err == os.EOF {
	break
	}
	die.Log(err)
	}
	parseScript(line[0:len(line)-1], table)
	}
	resp.Body.Close()

	// Find out which scripts to dump
	list := strings.Split(flaglist, ",", 0)
	if flaglist == "all" {
	list = all(table)
	}
	if *test {
	fullScriptTest(list, installed, table)
	return
	}

	fmt.Printf(
	"// Generated by running\n"+
	"// maketables --%s=%s --url=%s\n"+
	"// DO NOT EDIT\n\n",
	flag,
	flaglist,
	*url)
	if flaglist == "all" {
	if doProps {
	fmt.Println("// Properties is the set of Unicode property tables.")
	fmt.Println("var Properties = map[string] []Range {")
	} else {
	fmt.Println("// Scripts is the set of Unicode script tables.")
	fmt.Println("var Scripts = map[string] []Range {")
	}
	for k, _ := range table {
	fmt.Printf("\t%q: %s,\n", k, k)
	}
	fmt.Printf("}\n\n")
	}

	decl := make(sort.StringArray, len(list))
	ndecl := 0
	for _, name := range list {
	if doProps {
	decl[ndecl] = fmt.Sprintf(
	"\t%s = _%s;\t// %s is the set of Unicode characters with property %s.\n",
	name, name, name, name)
	} else {
	decl[ndecl] = fmt.Sprintf(
	"\t%s = _%s;\t// %s is the set of Unicode characters in script %s.\n",
	name, name, name, name)
	}
	ndecl++
	fmt.Printf("var _%s = []Range {\n", name)
	ranges := foldAdjacent(table[name])
	for _, s := range ranges {
	fmt.Printf(format, s.Lo, s.Hi, s.Stride)
	}
	fmt.Printf("}\n\n")
	}
	decl.Sort()
	fmt.Println("var (")
	for _, d := range decl {
	fmt.Print(d)
	}
	fmt.Println(")\n")
	}

	const (
	CaseUpper = 1 << iota
	CaseLower
	CaseTitle
	CaseNone = 0 // must be zero
	CaseMissing = -1 // character not present; not a valid case state
	)

	type caseState struct {
	point int
	_case int
	deltaToUpper int
	deltaToLower int
	deltaToTitle int
	}

	// Is d a continuation of the state of c?
	func (c caseState) adjacent(d caseState) bool {
	if d.point < c.point {
	c, d = d, c
	}
	switch {
	case d.point != c.point+1: // code points not adjacent (shouldn't happen)
	return false
	case d._case != c._case: // different cases
	return c.upperLowerAdjacent(d)
	case c._case == CaseNone:
	return false
	case c._case == CaseMissing:
	return false
	case d.deltaToUpper != c.deltaToUpper:
	return false
	case d.deltaToLower != c.deltaToLower:
	return false
	case d.deltaToTitle != c.deltaToTitle:
	return false
	}
	return true
	}

	// Is d the same as c, but opposite in upper/lower case? this would make it
	// an element of an UpperLower sequence.
	func (c caseState) upperLowerAdjacent(d caseState) bool {
	// check they're a matched case pair. we know they have adjacent values
	switch {
	case c._case == CaseUpper && d._case != CaseLower:
	return false
	case c._case == CaseLower && d._case != CaseUpper:
	return false
	}
	// matched pair (at least in upper/lower). make the order Upper Lower
	if c._case == CaseLower {
	c, d = d, c
	}
	// for an Upper Lower sequence the deltas have to be in order
	// c: 0 1 0
	// d: -1 0 -1
	switch {
	case c.deltaToUpper != 0:
	return false
	case c.deltaToLower != 1:
	return false
	case c.deltaToTitle != 0:
	return false
	case d.deltaToUpper != -1:
	return false
	case d.deltaToLower != 0:
	return false
	case d.deltaToTitle != -1:
	return false
	}
	return true
	}

	// Does this character start an UpperLower sequence?
	func (c *caseState) isUpperLower() bool {
	// for an Upper Lower sequence the deltas have to be in order
	// c: 0 1 0
	switch {
	case c.deltaToUpper != 0:
	return false
	case c.deltaToLower != 1:
	return false
	case c.deltaToTitle != 0:
	return false
	}
	return true
	}

	// Does this character start a LowerUpper sequence?
	func (c *caseState) isLowerUpper() bool {
	// for an Upper Lower sequence the deltas have to be in order
	// c: -1 0 -1
	switch {
	case c.deltaToUpper != -1:
	return false
	case c.deltaToLower != 0:
	return false
	case c.deltaToTitle != -1:
	return false
	}
	return true
	}

	func getCaseState(i int) (c *caseState) {
	c = &caseState{point: i, _case: CaseNone}
	ch := &chars[i]
	switch int(ch.codePoint) {
	case 0:
	c._case = CaseMissing // Will get NUL wrong but that doesn't matter
	return
	case ch.upperCase:
	c._case = CaseUpper
	case ch.lowerCase:
	c._case = CaseLower
	case ch.titleCase:
	c._case = CaseTitle
	}
	if ch.upperCase != 0 {
	c.deltaToUpper = ch.upperCase - i
	}
	if ch.lowerCase != 0 {
	c.deltaToLower = ch.lowerCase - i
	}
	if ch.titleCase != 0 {
	c.deltaToTitle = ch.titleCase - i
	}
	return
	}

	func printCases() {
	if !*cases {
	return
	}
	if *test {
	fullCaseTest()
	return
	}
	fmt.Printf(
	"// Generated by running\n"+
	"// maketables --data=%s\n"+
	"// DO NOT EDIT\n\n"+
	"// CaseRanges is the table describing case mappings for all letters with\n"+
	"// non-self mappings.\n"+
	"var CaseRanges = _CaseRanges\n"+
	"var _CaseRanges = []CaseRange {\n",
	*dataURL)

	var startState *caseState // the start of a run; nil for not active
	var prevState = &caseState{} // the state of the previous character
	for i := range chars {
	state := getCaseState(i)
	if state.adjacent(prevState) {
	prevState = state
	continue
	}
	// end of run (possibly)
	printCaseRange(startState, prevState)
	startState = nil
	if state._case != CaseMissing && state._case != CaseNone {
	startState = state
	}
	prevState = state
	}
	fmt.Printf("}\n")
	}

	func printCaseRange(lo, hi *caseState) {
	if lo == nil {
	return
	}
	if lo.deltaToUpper == 0 && lo.deltaToLower == 0 && lo.deltaToTitle == 0 {
	// character represents itself in all cases - no need to mention it
	return
	}
	switch {
	case hi.point > lo.point && lo.isUpperLower():
	fmt.Printf("\tCaseRange{0x%04X, 0x%04X, d{UpperLower, UpperLower, UpperLower}},\n",
	lo.point, hi.point)
	case hi.point > lo.point && lo.isLowerUpper():
	die.Log("LowerUpper sequence: should not happen: U+%04X. If it's real, need to fix To()", lo.point)
	fmt.Printf("\tCaseRange{0x%04X, 0x%04X, d{LowerUpper, LowerUpper, LowerUpper}},\n",
	lo.point, hi.point)
	default:
	fmt.Printf("\tCaseRange{0x%04X, 0x%04X, d{%d, %d, %d}},\n",
	lo.point, hi.point,
	lo.deltaToUpper, lo.deltaToLower, lo.deltaToTitle)
	}
	}

	// If the cased value in the Char is 0, it means use the rune itself.
	func caseIt(rune, cased int) int {
	if cased == 0 {
	return rune
	}
	return cased
	}

	func fullCaseTest() {
	for i, c := range chars {
	lower := unicode.ToLower(i)
	want := caseIt(i, c.lowerCase)
	if lower != want {
	fmt.Fprintf(os.Stderr, "lower U+%04X should be U+%04X is U+%04X\n", i, want, lower)
	}
	upper := unicode.ToUpper(i)
	want = caseIt(i, c.upperCase)
	if upper != want {
	fmt.Fprintf(os.Stderr, "upper U+%04X should be U+%04X is U+%04X\n", i, want, upper)
	}
	title := unicode.ToTitle(i)
	want = caseIt(i, c.titleCase)
	if title != want {
	fmt.Fprintf(os.Stderr, "title U+%04X should be U+%04X is U+%04X\n", i, want, title)
	}
	}
	}