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skia / external / github.com / unicode-org / icu / refs/tags/icu-release-3-8 / . / source / i18n / nfrule.cpp
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/*
******************************************************************************
* Copyright (C) 1997-2006, International Business Machines
* Corporation and others. All Rights Reserved.
******************************************************************************
* file name: nfrule.cpp
* encoding: US-ASCII
* tab size: 8 (not used)
* indentation:4
*
* Modification history
* Date Name Comments
* 10/11/2001 Doug Ported from ICU4J
*/
#include "nfrule.h"
#if U_HAVE_RBNF
#include "unicode/rbnf.h"
#include "unicode/tblcoll.h"
#include "unicode/coleitr.h"
#include "unicode/uchar.h"
#include "nfrs.h"
#include "nfrlist.h"
#include "nfsubs.h"
#include "util.h"
U_NAMESPACE_BEGIN
NFRule::NFRule(const RuleBasedNumberFormat* _rbnf)
: baseValue((int32_t)0)
, radix(0)
, exponent(0)
, ruleText()
, sub1(NULL)
, sub2(NULL)
, formatter(_rbnf)
{
}
NFRule::~NFRule()
{
delete sub1;
delete sub2;
}
static const UChar gLeftBracket = 0x005b;
static const UChar gRightBracket = 0x005d;
static const UChar gColon = 0x003a;
static const UChar gZero = 0x0030;
static const UChar gNine = 0x0039;
static const UChar gSpace = 0x0020;
static const UChar gSlash = 0x002f;
static const UChar gGreaterThan = 0x003e;
static const UChar gLessThan = 0x003c;
static const UChar gComma = 0x002c;
static const UChar gDot = 0x002e;
static const UChar gTick = 0x0027;
//static const UChar gMinus = 0x002d;
static const UChar gSemicolon = 0x003b;
static const UChar gMinusX[] = {0x2D, 0x78, 0}; /* "-x" */
static const UChar gXDotX[] = {0x78, 0x2E, 0x78, 0}; /* "x.x" */
static const UChar gXDotZero[] = {0x78, 0x2E, 0x30, 0}; /* "x.0" */
static const UChar gZeroDotX[] = {0x30, 0x2E, 0x78, 0}; /* "0.x" */
static const UChar gLessLess[] = {0x3C, 0x3C, 0}; /* "<<" */
static const UChar gLessPercent[] = {0x3C, 0x25, 0}; /* "<%" */
static const UChar gLessHash[] = {0x3C, 0x23, 0}; /* "<#" */
static const UChar gLessZero[] = {0x3C, 0x30, 0}; /* "<0" */
static const UChar gGreaterGreater[] = {0x3E, 0x3E, 0}; /* ">>" */
static const UChar gGreaterPercent[] = {0x3E, 0x25, 0}; /* ">%" */
static const UChar gGreaterHash[] = {0x3E, 0x23, 0}; /* ">#" */
static const UChar gGreaterZero[] = {0x3E, 0x30, 0}; /* ">0" */
static const UChar gEqualPercent[] = {0x3D, 0x25, 0}; /* "=%" */
static const UChar gEqualHash[] = {0x3D, 0x23, 0}; /* "=#" */
static const UChar gEqualZero[] = {0x3D, 0x30, 0}; /* "=0" */
static const UChar gEmptyString[] = {0}; /* "" */
static const UChar gGreaterGreaterGreater[] = {0x3E, 0x3E, 0x3E, 0}; /* ">>>" */
static const UChar * const tokenStrings[] = {
gLessLess, gLessPercent, gLessHash, gLessZero,
gGreaterGreater, gGreaterPercent,gGreaterHash, gGreaterZero,
gEqualPercent, gEqualHash, gEqualZero, NULL
};
void
NFRule::makeRules(UnicodeString& description,
const NFRuleSet *ruleSet,
const NFRule *predecessor,
const RuleBasedNumberFormat *rbnf,
NFRuleList& rules,
UErrorCode& status)
{
// we know we're making at least one rule, so go ahead and
// new it up and initialize its basevalue and divisor
// (this also strips the rule descriptor, if any, off the
// descripton string)
NFRule* rule1 = new NFRule(rbnf);
/* test for NULL */
if (rule1 == 0) {
status = U_MEMORY_ALLOCATION_ERROR;
return;
}
rule1->parseRuleDescriptor(description, status);
// check the description to see whether there's text enclosed
// in brackets
int32_t brack1 = description.indexOf(gLeftBracket);
int32_t brack2 = description.indexOf(gRightBracket);
// if the description doesn't contain a matched pair of brackets,
// or if it's of a type that doesn't recognize bracketed text,
// then leave the description alone, initialize the rule's
// rule text and substitutions, and return that rule
if (brack1 == -1 || brack2 == -1 || brack1 > brack2
|| rule1->getType() == kProperFractionRule
|| rule1->getType() == kNegativeNumberRule) {
rule1->ruleText = description;
rule1->extractSubstitutions(ruleSet, predecessor, rbnf, status);
rules.add(rule1);
} else {
// if the description does contain a matched pair of brackets,
// then it's really shorthand for two rules (with one exception)
NFRule* rule2 = NULL;
UnicodeString sbuf;
// we'll actually only split the rule into two rules if its
// base value is an even multiple of its divisor (or it's one
// of the special rules)
if ((rule1->baseValue > 0
&& (rule1->baseValue % util64_pow(rule1->radix, rule1->exponent)) == 0)
|| rule1->getType() == kImproperFractionRule
|| rule1->getType() == kMasterRule) {
// if it passes that test, new up the second rule. If the
// rule set both rules will belong to is a fraction rule
// set, they both have the same base value; otherwise,
// increment the original rule's base value ("rule1" actually
// goes SECOND in the rule set's rule list)
rule2 = new NFRule(rbnf);
/* test for NULL */
if (rule2 == 0) {
status = U_MEMORY_ALLOCATION_ERROR;
return;
}
if (rule1->baseValue >= 0) {
rule2->baseValue = rule1->baseValue;
if (!ruleSet->isFractionRuleSet()) {
++rule1->baseValue;
}
}
// if the description began with "x.x" and contains bracketed
// text, it describes both the improper fraction rule and
// the proper fraction rule
else if (rule1->getType() == kImproperFractionRule) {
rule2->setType(kProperFractionRule);
}
// if the description began with "x.0" and contains bracketed
// text, it describes both the master rule and the
// improper fraction rule
else if (rule1->getType() == kMasterRule) {
rule2->baseValue = rule1->baseValue;
rule1->setType(kImproperFractionRule);
}
// both rules have the same radix and exponent (i.e., the
// same divisor)
rule2->radix = rule1->radix;
rule2->exponent = rule1->exponent;
// rule2's rule text omits the stuff in brackets: initalize
// its rule text and substitutions accordingly
sbuf.append(description, 0, brack1);
if (brack2 + 1 < description.length()) {
sbuf.append(description, brack2 + 1, description.length() - brack2 - 1);
}
rule2->ruleText.setTo(sbuf);
rule2->extractSubstitutions(ruleSet, predecessor, rbnf, status);
}
// rule1's text includes the text in the brackets but omits
// the brackets themselves: initialize _its_ rule text and
// substitutions accordingly
sbuf.setTo(description, 0, brack1);
sbuf.append(description, brack1 + 1, brack2 - brack1 - 1);
if (brack2 + 1 < description.length()) {
sbuf.append(description, brack2 + 1, description.length() - brack2 - 1);
}
rule1->ruleText.setTo(sbuf);
rule1->extractSubstitutions(ruleSet, predecessor, rbnf, status);
// if we only have one rule, return it; if we have two, return
// a two-element array containing them (notice that rule2 goes
// BEFORE rule1 in the list: in all cases, rule2 OMITS the
// material in the brackets and rule1 INCLUDES the material
// in the brackets)
if (rule2 != NULL) {
rules.add(rule2);
}
rules.add(rule1);
}
}
/**
* This function parses the rule's rule descriptor (i.e., the base
* value and/or other tokens that precede the rule's rule text
* in the description) and sets the rule's base value, radix, and
* exponent according to the descriptor. (If the description doesn't
* include a rule descriptor, then this function sets everything to
* default values and the rule set sets the rule's real base value).
* @param description The rule's description
* @return If "description" included a rule descriptor, this is
* "description" with the descriptor and any trailing whitespace
* stripped off. Otherwise; it's "descriptor" unchangd.
*/
void
NFRule::parseRuleDescriptor(UnicodeString& description, UErrorCode& status)
{
// the description consists of a rule descriptor and a rule body,
// separated by a colon. The rule descriptor is optional. If
// it's omitted, just set the base value to 0.
int32_t p = description.indexOf(gColon);
if (p == -1) {
setBaseValue((int32_t)0, status);
} else {
// copy the descriptor out into its own string and strip it,
// along with any trailing whitespace, out of the original
// description
UnicodeString descriptor;
descriptor.setTo(description, 0, p);
++p;
while (p < description.length() && uprv_isRuleWhiteSpace(description.charAt(p))) {
++p;
}
description.removeBetween(0, p);
// check first to see if the rule descriptor matches the token
// for one of the special rules. If it does, set the base
// value to the correct identfier value
if (descriptor == gMinusX) {
setType(kNegativeNumberRule);
}
else if (descriptor == gXDotX) {
setType(kImproperFractionRule);
}
else if (descriptor == gZeroDotX) {
setType(kProperFractionRule);
}
else if (descriptor == gXDotZero) {
setType(kMasterRule);
}
// if the rule descriptor begins with a digit, it's a descriptor
// for a normal rule
// since we don't have Long.parseLong, and this isn't much work anyway,
// just build up the value as we encounter the digits.
else if (descriptor.charAt(0) >= gZero && descriptor.charAt(0) <= gNine) {
int64_t val = 0;
p = 0;
UChar c = gSpace;
// begin parsing the descriptor: copy digits
// into "tempValue", skip periods, commas, and spaces,
// stop on a slash or > sign (or at the end of the string),
// and throw an exception on any other character
int64_t ll_10 = 10;
while (p < descriptor.length()) {
c = descriptor.charAt(p);
if (c >= gZero && c <= gNine) {
val = val * ll_10 + (int32_t)(c - gZero);
}
else if (c == gSlash || c == gGreaterThan) {
break;
}
else if (uprv_isRuleWhiteSpace(c) || c == gComma || c == gDot) {
}
else {
// throw new IllegalArgumentException("Illegal character in rule descriptor");
status = U_PARSE_ERROR;
return;
}
++p;
}
// we have the base value, so set it
setBaseValue(val, status);
// if we stopped the previous loop on a slash, we're
// now parsing the rule's radix. Again, accumulate digits
// in tempValue, skip punctuation, stop on a > mark, and
// throw an exception on anything else
if (c == gSlash) {
val = 0;
++p;
int64_t ll_10 = 10;
while (p < descriptor.length()) {
c = descriptor.charAt(p);
if (c >= gZero && c <= gNine) {
val = val * ll_10 + (int32_t)(c - gZero);
}
else if (c == gGreaterThan) {
break;
}
else if (uprv_isRuleWhiteSpace(c) || c == gComma || c == gDot) {
}
else {
// throw new IllegalArgumentException("Illegal character is rule descriptor");
status = U_PARSE_ERROR;
return;
}
++p;
}
// tempValue now contain's the rule's radix. Set it
// accordingly, and recalculate the rule's exponent
radix = (int32_t)val;
if (radix == 0) {
// throw new IllegalArgumentException("Rule can't have radix of 0");
status = U_PARSE_ERROR;
}
exponent = expectedExponent();
}
// if we stopped the previous loop on a > sign, then continue
// for as long as we still see > signs. For each one,
// decrement the exponent (unless the exponent is already 0).
// If we see another character before reaching the end of
// the descriptor, that's also a syntax error.
if (c == gGreaterThan) {
while (p < descriptor.length()) {
c = descriptor.charAt(p);
if (c == gGreaterThan && exponent > 0) {
--exponent;
} else {
// throw new IllegalArgumentException("Illegal character in rule descriptor");
status = U_PARSE_ERROR;
return;
}
++p;
}
}
}
}
// finally, if the rule body begins with an apostrophe, strip it off
// (this is generally used to put whitespace at the beginning of
// a rule's rule text)
if (description.length() > 0 && description.charAt(0) == gTick) {
description.removeBetween(0, 1);
}
// return the description with all the stuff we've just waded through
// stripped off the front. It now contains just the rule body.
// return description;
}
/**
* Searches the rule's rule text for the substitution tokens,
* creates the substitutions, and removes the substitution tokens
* from the rule's rule text.
* @param owner The rule set containing this rule
* @param predecessor The rule preseding this one in "owners" rule list
* @param ownersOwner The RuleBasedFormat that owns this rule
*/
void
NFRule::extractSubstitutions(const NFRuleSet* ruleSet,
const NFRule* predecessor,
const RuleBasedNumberFormat* rbnf,
UErrorCode& status)
{
if (U_SUCCESS(status)) {
sub1 = extractSubstitution(ruleSet, predecessor, rbnf, status);
sub2 = extractSubstitution(ruleSet, predecessor, rbnf, status);
}
}
/**
* Searches the rule's rule text for the first substitution token,
* creates a substitution based on it, and removes the token from
* the rule's rule text.
* @param owner The rule set containing this rule
* @param predecessor The rule preceding this one in the rule set's
* rule list
* @param ownersOwner The RuleBasedNumberFormat that owns this rule
* @return The newly-created substitution. This is never null; if
* the rule text doesn't contain any substitution tokens, this will
* be a NullSubstitution.
*/
NFSubstitution *
NFRule::extractSubstitution(const NFRuleSet* ruleSet,
const NFRule* predecessor,
const RuleBasedNumberFormat* rbnf,
UErrorCode& status)
{
NFSubstitution* result = NULL;
// search the rule's rule text for the first two characters of
// a substitution token
int32_t subStart = indexOfAny(tokenStrings);
int32_t subEnd = subStart;
// if we didn't find one, create a null substitution positioned
// at the end of the rule text
if (subStart == -1) {
return NFSubstitution::makeSubstitution(ruleText.length(), this, predecessor,
ruleSet, rbnf, gEmptyString, status);
}
// special-case the ">>>" token, since searching for the > at the
// end will actually find the > in the middle
if (ruleText.indexOf(gGreaterGreaterGreater) == subStart) {
subEnd = subStart + 2;
// otherwise the substitution token ends with the same character
// it began with
} else {
UChar c = ruleText.charAt(subStart);
subEnd = ruleText.indexOf(c, subStart + 1);
// special case for '<%foo<<'
if (c == gLessThan && subEnd != -1 && subEnd < ruleText.length() - 1 && ruleText.charAt(subEnd+1) == c) {
// ordinals use "=#,##0==%abbrev=" as their rule. Notice that the '==' in the middle
// occurs because of the juxtaposition of two different rules. The check for '<' is a hack
// to get around this. Having the duplicate at the front would cause problems with
// rules like "<<%" to format, say, percents...
++subEnd;
}
}
// if we don't find the end of the token (i.e., if we're on a single,
// unmatched token character), create a null substitution positioned
// at the end of the rule
if (subEnd == -1) {
return NFSubstitution::makeSubstitution(ruleText.length(), this, predecessor,
ruleSet, rbnf, gEmptyString, status);
}
// if we get here, we have a real substitution token (or at least
// some text bounded by substitution token characters). Use
// makeSubstitution() to create the right kind of substitution
UnicodeString subToken;
subToken.setTo(ruleText, subStart, subEnd + 1 - subStart);
result = NFSubstitution::makeSubstitution(subStart, this, predecessor, ruleSet,
rbnf, subToken, status);
// remove the substitution from the rule text
ruleText.removeBetween(subStart, subEnd+1);
return result;
}
/**
* Sets the rule's base value, and causes the radix and exponent
* to be recalculated. This is used during construction when we
* don't know the rule's base value until after it's been
* constructed. It should be used at any other time.
* @param The new base value for the rule.
*/
void
NFRule::setBaseValue(int64_t newBaseValue, UErrorCode& status)
{
// set the base value
baseValue = newBaseValue;
// if this isn't a special rule, recalculate the radix and exponent
// (the radix always defaults to 10; if it's supposed to be something
// else, it's cleaned up by the caller and the exponent is
// recalculated again-- the only function that does this is
// NFRule.parseRuleDescriptor() )
if (baseValue >= 1) {
radix = 10;
exponent = expectedExponent();
// this function gets called on a fully-constructed rule whose
// description didn't specify a base value. This means it
// has substitutions, and some substitutions hold on to copies
// of the rule's divisor. Fix their copies of the divisor.
if (sub1 != NULL) {
sub1->setDivisor(radix, exponent, status);
}
if (sub2 != NULL) {
sub2->setDivisor(radix, exponent, status);
}
// if this is a special rule, its radix and exponent are basically
// ignored. Set them to "safe" default values
} else {
radix = 10;
exponent = 0;
}
}
/**
* This calculates the rule's exponent based on its radix and base
* value. This will be the highest power the radix can be raised to
* and still produce a result less than or equal to the base value.
*/
int16_t
NFRule::expectedExponent() const
{
// since the log of 0, or the log base 0 of something, causes an
// error, declare the exponent in these cases to be 0 (we also
// deal with the special-rule identifiers here)
if (radix == 0 || baseValue < 1) {
return 0;
}
// we get rounding error in some cases-- for example, log 1000 / log 10
// gives us 1.9999999996 instead of 2. The extra logic here is to take
// that into account
int16_t tempResult = (int16_t)(uprv_log((double)baseValue) / uprv_log((double)radix));
int64_t temp = util64_pow(radix, tempResult + 1);
if (temp <= baseValue) {
tempResult += 1;
}
return tempResult;
}
/**
* Searches the rule's rule text for any of the specified strings.
* @param strings An array of strings to search the rule's rule
* text for
* @return The index of the first match in the rule's rule text
* (i.e., the first substring in the rule's rule text that matches
* _any_ of the strings in "strings"). If none of the strings in
* "strings" is found in the rule's rule text, returns -1.
*/
int32_t
NFRule::indexOfAny(const UChar* const strings[]) const
{
int result = -1;
for (int i = 0; strings[i]; i++) {
int32_t pos = ruleText.indexOf(*strings[i]);
if (pos != -1 && (result == -1 || pos < result)) {
result = pos;
}
}
return result;
}
//-----------------------------------------------------------------------
// boilerplate
//-----------------------------------------------------------------------
/**
* Tests two rules for equality.
* @param that The rule to compare this one against
* @return True is the two rules are functionally equivalent
*/
UBool
NFRule::operator==(const NFRule& rhs) const
{
return baseValue == rhs.baseValue
&& radix == rhs.radix
&& exponent == rhs.exponent
&& ruleText == rhs.ruleText
&& *sub1 == *rhs.sub1
&& *sub2 == *rhs.sub2;
}
/**
* Returns a textual representation of the rule. This won't
* necessarily be the same as the description that this rule
* was created with, but it will produce the same result.
* @return A textual description of the rule
*/
static void util_append64(UnicodeString& result, int64_t n)
{
UChar buffer[256];
int32_t len = util64_tou(n, buffer, sizeof(buffer));
UnicodeString temp(buffer, len);
result.append(temp);
}
void
NFRule::_appendRuleText(UnicodeString& result) const
{
switch (getType()) {
case kNegativeNumberRule: result.append(gMinusX); break;
case kImproperFractionRule: result.append(gXDotX); break;
case kProperFractionRule: result.append(gZeroDotX); break;
case kMasterRule: result.append(gXDotZero); break;
default:
// for a normal rule, write out its base value, and if the radix is
// something other than 10, write out the radix (with the preceding
// slash, of course). Then calculate the expected exponent and if
// if isn't the same as the actual exponent, write an appropriate
// number of > signs. Finally, terminate the whole thing with
// a colon.
util_append64(result, baseValue);
if (radix != 10) {
result.append(gSlash);
util_append64(result, radix);
}
int numCarets = expectedExponent() - exponent;
for (int i = 0; i < numCarets; i++) {
result.append(gGreaterThan);
}
break;
}
result.append(gColon);
result.append(gSpace);
// if the rule text begins with a space, write an apostrophe
// (whitespace after the rule descriptor is ignored; the
// apostrophe is used to make the whitespace significant)
if (ruleText.startsWith(gSpace) && sub1->getPos() != 0) {
result.append(gTick);
}
// now, write the rule's rule text, inserting appropriate
// substitution tokens in the appropriate places
UnicodeString ruleTextCopy;
ruleTextCopy.setTo(ruleText);
UnicodeString temp;
sub2->toString(temp);
ruleTextCopy.insert(sub2->getPos(), temp);
sub1->toString(temp);
ruleTextCopy.insert(sub1->getPos(), temp);
result.append(ruleTextCopy);
// and finally, top the whole thing off with a semicolon and
// return the result
result.append(gSemicolon);
}
//-----------------------------------------------------------------------
// formatting
//-----------------------------------------------------------------------
/**
* Formats the number, and inserts the resulting text into
* toInsertInto.
* @param number The number being formatted
* @param toInsertInto The string where the resultant text should
* be inserted
* @param pos The position in toInsertInto where the resultant text
* should be inserted
*/
void
NFRule::doFormat(int64_t number, UnicodeString& toInsertInto, int32_t pos) const
{
// first, insert the rule's rule text into toInsertInto at the
// specified position, then insert the results of the substitutions
// into the right places in toInsertInto (notice we do the
// substitutions in reverse order so that the offsets don't get
// messed up)
toInsertInto.insert(pos, ruleText);
sub2->doSubstitution(number, toInsertInto, pos);
sub1->doSubstitution(number, toInsertInto, pos);
}
/**
* Formats the number, and inserts the resulting text into
* toInsertInto.
* @param number The number being formatted
* @param toInsertInto The string where the resultant text should
* be inserted
* @param pos The position in toInsertInto where the resultant text
* should be inserted
*/
void
NFRule::doFormat(double number, UnicodeString& toInsertInto, int32_t pos) const
{
// first, insert the rule's rule text into toInsertInto at the
// specified position, then insert the results of the substitutions
// into the right places in toInsertInto
// [again, we have two copies of this routine that do the same thing
// so that we don't sacrifice precision in a long by casting it
// to a double]
toInsertInto.insert(pos, ruleText);
sub2->doSubstitution(number, toInsertInto, pos);
sub1->doSubstitution(number, toInsertInto, pos);
}
/**
* Used by the owning rule set to determine whether to invoke the
* rollback rule (i.e., whether this rule or the one that precedes
* it in the rule set's list should be used to format the number)
* @param The number being formatted
* @return True if the rule set should use the rule that precedes
* this one in its list; false if it should use this rule
*/
UBool
NFRule::shouldRollBack(double number) const
{
// we roll back if the rule contains a modulus substitution,
// the number being formatted is an even multiple of the rule's
// divisor, and the rule's base value is NOT an even multiple
// of its divisor
// In other words, if the original description had
// 100: << hundred[ >>];
// that expands into
// 100: << hundred;
// 101: << hundred >>;
// internally. But when we're formatting 200, if we use the rule
// at 101, which would normally apply, we get "two hundred zero".
// To prevent this, we roll back and use the rule at 100 instead.
// This is the logic that makes this happen: the rule at 101 has
// a modulus substitution, its base value isn't an even multiple
// of 100, and the value we're trying to format _is_ an even
// multiple of 100. This is called the "rollback rule."
if ((sub1->isModulusSubstitution()) || (sub2->isModulusSubstitution())) {
int64_t re = util64_pow(radix, exponent);
return uprv_fmod(number, (double)re) == 0 && (baseValue % re) != 0;
}
return FALSE;
}
//-----------------------------------------------------------------------
// parsing
//-----------------------------------------------------------------------
/**
* Attempts to parse the string with this rule.
* @param text The string being parsed
* @param parsePosition On entry, the value is ignored and assumed to
* be 0. On exit, this has been updated with the position of the first
* character not consumed by matching the text against this rule
* (if this rule doesn't match the text at all, the parse position
* if left unchanged (presumably at 0) and the function returns
* new Long(0)).
* @param isFractionRule True if this rule is contained within a
* fraction rule set. This is only used if the rule has no
* substitutions.
* @return If this rule matched the text, this is the rule's base value
* combined appropriately with the results of parsing the substitutions.
* If nothing matched, this is new Long(0) and the parse position is
* left unchanged. The result will be an instance of Long if the
* result is an integer and Double otherwise. The result is never null.
*/
#ifdef RBNF_DEBUG
#include <stdio.h>
static void dumpUS(FILE* f, const UnicodeString& us) {
int len = us.length();
char* buf = (char *)uprv_malloc((len+1)*sizeof(char)); //new char[len+1];
us.extract(0, len, buf);
buf[len] = 0;
fprintf(f, "%s", buf);
uprv_free(buf); //delete[] buf;
}
#endif
UBool
NFRule::doParse(const UnicodeString& text,
ParsePosition& parsePosition,
UBool isFractionRule,
double upperBound,
Formattable& resVal) const
{
// internally we operate on a copy of the string being parsed
// (because we're going to change it) and use our own ParsePosition
ParsePosition pp;
UnicodeString workText(text);
// check to see whether the text before the first substitution
// matches the text at the beginning of the string being
// parsed. If it does, strip that off the front of workText;
// otherwise, dump out with a mismatch
UnicodeString prefix;
prefix.setTo(ruleText, 0, sub1->getPos());
#ifdef RBNF_DEBUG
fprintf(stderr, "doParse %x ", this);
{
UnicodeString rt;
_appendRuleText(rt);
dumpUS(stderr, rt);
}
fprintf(stderr, " text: '", this);
dumpUS(stderr, text);
fprintf(stderr, "' prefix: '");
dumpUS(stderr, prefix);
#endif
stripPrefix(workText, prefix, pp);
int32_t prefixLength = text.length() - workText.length();
#ifdef RBNF_DEBUG
fprintf(stderr, "' pl: %d ppi: %d s1p: %d\n", prefixLength, pp.getIndex(), sub1->getPos());
#endif
if (pp.getIndex() == 0 && sub1->getPos() != 0) {
// commented out because ParsePosition doesn't have error index in 1.1.x
// restored for ICU4C port
parsePosition.setErrorIndex(pp.getErrorIndex());
resVal.setLong(0);
return TRUE;
}
// this is the fun part. The basic guts of the rule-matching
// logic is matchToDelimiter(), which is called twice. The first
// time it searches the input string for the rule text BETWEEN
// the substitutions and tries to match the intervening text
// in the input string with the first substitution. If that
// succeeds, it then calls it again, this time to look for the
// rule text after the second substitution and to match the
// intervening input text against the second substitution.
//
// For example, say we have a rule that looks like this:
// first << middle >> last;
// and input text that looks like this:
// first one middle two last
// First we use stripPrefix() to match "first " in both places and
// strip it off the front, leaving
// one middle two last
// Then we use matchToDelimiter() to match " middle " and try to
// match "one" against a substitution. If it's successful, we now
// have
// two last
// We use matchToDelimiter() a second time to match " last" and
// try to match "two" against a substitution. If "two" matches
// the substitution, we have a successful parse.
//
// Since it's possible in many cases to find multiple instances
// of each of these pieces of rule text in the input string,
// we need to try all the possible combinations of these
// locations. This prevents us from prematurely declaring a mismatch,
// and makes sure we match as much input text as we can.
int highWaterMark = 0;
double result = 0;
int start = 0;
double tempBaseValue = (double)(baseValue <= 0 ? 0 : baseValue);
UnicodeString temp;
do {
// our partial parse result starts out as this rule's base
// value. If it finds a successful match, matchToDelimiter()
// will compose this in some way with what it gets back from
// the substitution, giving us a new partial parse result
pp.setIndex(0);
temp.setTo(ruleText, sub1->getPos(), sub2->getPos() - sub1->getPos());
double partialResult = matchToDelimiter(workText, start, tempBaseValue,
temp, pp, sub1,
upperBound);
// if we got a successful match (or were trying to match a
// null substitution), pp is now pointing at the first unmatched
// character. Take note of that, and try matchToDelimiter()
// on the input text again
if (pp.getIndex() != 0 || sub1->isNullSubstitution()) {
start = pp.getIndex();
UnicodeString workText2;
workText2.setTo(workText, pp.getIndex(), workText.length() - pp.getIndex());
ParsePosition pp2;
// the second matchToDelimiter() will compose our previous
// partial result with whatever it gets back from its
// substitution if there's a successful match, giving us
// a real result
temp.setTo(ruleText, sub2->getPos(), ruleText.length() - sub2->getPos());
partialResult = matchToDelimiter(workText2, 0, partialResult,
temp, pp2, sub2,
upperBound);
// if we got a successful match on this second
// matchToDelimiter() call, update the high-water mark
// and result (if necessary)
if (pp2.getIndex() != 0 || sub2->isNullSubstitution()) {
if (prefixLength + pp.getIndex() + pp2.getIndex() > highWaterMark) {
highWaterMark = prefixLength + pp.getIndex() + pp2.getIndex();
result = partialResult;
}
}
// commented out because ParsePosition doesn't have error index in 1.1.x
// restored for ICU4C port
else {
int32_t temp = pp2.getErrorIndex() + sub1->getPos() + pp.getIndex();
if (temp> parsePosition.getErrorIndex()) {
parsePosition.setErrorIndex(temp);
}
}
}
// commented out because ParsePosition doesn't have error index in 1.1.x
// restored for ICU4C port
else {
int32_t temp = sub1->getPos() + pp.getErrorIndex();
if (temp > parsePosition.getErrorIndex()) {
parsePosition.setErrorIndex(temp);
}
}
// keep trying to match things until the outer matchToDelimiter()
// call fails to make a match (each time, it picks up where it
// left off the previous time)
} while (sub1->getPos() != sub2->getPos()
&& pp.getIndex() > 0
&& pp.getIndex() < workText.length()
&& pp.getIndex() != start);
// update the caller's ParsePosition with our high-water mark
// (i.e., it now points at the first character this function
// didn't match-- the ParsePosition is therefore unchanged if
// we didn't match anything)
parsePosition.setIndex(highWaterMark);
// commented out because ParsePosition doesn't have error index in 1.1.x
// restored for ICU4C port
if (highWaterMark > 0) {
parsePosition.setErrorIndex(0);
}
// this is a hack for one unusual condition: Normally, whether this
// rule belong to a fraction rule set or not is handled by its
// substitutions. But if that rule HAS NO substitutions, then
// we have to account for it here. By definition, if the matching
// rule in a fraction rule set has no substitutions, its numerator
// is 1, and so the result is the reciprocal of its base value.
if (isFractionRule &&
highWaterMark > 0 &&
sub1->isNullSubstitution()) {
result = 1 / result;
}
resVal.setDouble(result);
return TRUE; // ??? do we need to worry if it is a long or a double?
}
/**
* This function is used by parse() to match the text being parsed
* against a possible prefix string. This function
* matches characters from the beginning of the string being parsed
* to characters from the prospective prefix. If they match, pp is
* updated to the first character not matched, and the result is
* the unparsed part of the string. If they don't match, the whole
* string is returned, and pp is left unchanged.
* @param text The string being parsed
* @param prefix The text to match against
* @param pp On entry, ignored and assumed to be 0. On exit, points
* to the first unmatched character (assuming the whole prefix matched),
* or is unchanged (if the whole prefix didn't match).
* @return If things match, this is the unparsed part of "text";
* if they didn't match, this is "text".
*/
void
NFRule::stripPrefix(UnicodeString& text, const UnicodeString& prefix, ParsePosition& pp) const
{
// if the prefix text is empty, dump out without doing anything
if (prefix.length() != 0) {
// use prefixLength() to match the beginning of
// "text" against "prefix". This function returns the
// number of characters from "text" that matched (or 0 if
// we didn't match the whole prefix)
int32_t pfl = prefixLength(text, prefix);
if (pfl != 0) {
// if we got a successful match, update the parse position
// and strip the prefix off of "text"
pp.setIndex(pp.getIndex() + pfl);
text.remove(0, pfl);
}
}
}
/**
* Used by parse() to match a substitution and any following text.
* "text" is searched for instances of "delimiter". For each instance
* of delimiter, the intervening text is tested to see whether it
* matches the substitution. The longest match wins.
* @param text The string being parsed
* @param startPos The position in "text" where we should start looking
* for "delimiter".
* @param baseValue A partial parse result (often the rule's base value),
* which is combined with the result from matching the substitution
* @param delimiter The string to search "text" for.
* @param pp Ignored and presumed to be 0 on entry. If there's a match,
* on exit this will point to the first unmatched character.
* @param sub If we find "delimiter" in "text", this substitution is used
* to match the text between the beginning of the string and the
* position of "delimiter." (If "delimiter" is the empty string, then
* this function just matches against this substitution and updates
* everything accordingly.)
* @param upperBound When matching the substitution, it will only
* consider rules with base values lower than this value.
* @return If there's a match, this is the result of composing
* baseValue with the result of matching the substitution. Otherwise,
* this is new Long(0). It's never null. If the result is an integer,
* this will be an instance of Long; otherwise, it's an instance of
* Double.
*
* !!! note {dlf} in point of fact, in the java code the caller always converts
* the result to a double, so we might as well return one.
*/
double
NFRule::matchToDelimiter(const UnicodeString& text,
int32_t startPos,
double _baseValue,
const UnicodeString& delimiter,
ParsePosition& pp,
const NFSubstitution* sub,
double upperBound) const
{
// if "delimiter" contains real (i.e., non-ignorable) text, search
// it for "delimiter" beginning at "start". If that succeeds, then
// use "sub"'s doParse() method to match the text before the
// instance of "delimiter" we just found.
if (!allIgnorable(delimiter)) {
ParsePosition tempPP;
Formattable result;
// use findText() to search for "delimiter". It returns a two-
// element array: element 0 is the position of the match, and
// element 1 is the number of characters that matched
// "delimiter".
int32_t dLen;
int32_t dPos = findText(text, delimiter, startPos, &dLen);
// if findText() succeeded, isolate the text preceding the
// match, and use "sub" to match that text
while (dPos >= 0) {
UnicodeString subText;
subText.setTo(text, 0, dPos);
if (subText.length() > 0) {
UBool success = sub->doParse(subText, tempPP, _baseValue, upperBound,
#if UCONFIG_NO_COLLATION
FALSE,
#else
formatter->isLenient(),
#endif
result);
// if the substitution could match all the text up to
// where we found "delimiter", then this function has
// a successful match. Bump the caller's parse position
// to point to the first character after the text
// that matches "delimiter", and return the result
// we got from parsing the substitution.
if (success && tempPP.getIndex() == dPos) {
pp.setIndex(dPos + dLen);
return result.getDouble();
}
// commented out because ParsePosition doesn't have error index in 1.1.x
// restored for ICU4C port
else {
if (tempPP.getErrorIndex() > 0) {
pp.setErrorIndex(tempPP.getErrorIndex());
} else {
pp.setErrorIndex(tempPP.getIndex());
}
}
}
// if we didn't match the substitution, search for another
// copy of "delimiter" in "text" and repeat the loop if
// we find it
tempPP.setIndex(0);
dPos = findText(text, delimiter, dPos + dLen, &dLen);
}
// if we make it here, this was an unsuccessful match, and we
// leave pp unchanged and return 0
pp.setIndex(0);
return 0;
// if "delimiter" is empty, or consists only of ignorable characters
// (i.e., is semantically empty), thwe we obviously can't search
// for "delimiter". Instead, just use "sub" to parse as much of
// "text" as possible.
} else {
ParsePosition tempPP;
Formattable result;
// try to match the whole string against the substitution
UBool success = sub->doParse(text, tempPP, _baseValue, upperBound,
#if UCONFIG_NO_COLLATION
FALSE,
#else
formatter->isLenient(),
#endif
result);
if (success && (tempPP.getIndex() != 0 || sub->isNullSubstitution())) {
// if there's a successful match (or it's a null
// substitution), update pp to point to the first
// character we didn't match, and pass the result from
// sub.doParse() on through to the caller
pp.setIndex(tempPP.getIndex());
return result.getDouble();
}
// commented out because ParsePosition doesn't have error index in 1.1.x
// restored for ICU4C port
else {
pp.setErrorIndex(tempPP.getErrorIndex());
}
// and if we get to here, then nothing matched, so we return
// 0 and leave pp alone
return 0;
}
}
/**
* Used by stripPrefix() to match characters. If lenient parse mode
* is off, this just calls startsWith(). If lenient parse mode is on,
* this function uses CollationElementIterators to match characters in
* the strings (only primary-order differences are significant in
* determining whether there's a match).
* @param str The string being tested
* @param prefix The text we're hoping to see at the beginning
* of "str"
* @return If "prefix" is found at the beginning of "str", this
* is the number of characters in "str" that were matched (this
* isn't necessarily the same as the length of "prefix" when matching
* text with a collator). If there's no match, this is 0.
*/
int32_t
NFRule::prefixLength(const UnicodeString& str, const UnicodeString& prefix) const
{
// if we're looking for an empty prefix, it obviously matches
// zero characters. Just go ahead and return 0.
if (prefix.length() == 0) {
return 0;
}
#if !UCONFIG_NO_COLLATION
// go through all this grief if we're in lenient-parse mode
if (formatter->isLenient()) {
// get the formatter's collator and use it to create two
// collation element iterators, one over the target string
// and another over the prefix (right now, we'll throw an
// exception if the collator we get back from the formatter
// isn't a RuleBasedCollator, because RuleBasedCollator defines
// the CollationElementIterator protocol. Hopefully, this
// will change someday.)
RuleBasedCollator* collator = (RuleBasedCollator*)formatter->getCollator();
CollationElementIterator* strIter = collator->createCollationElementIterator(str);
CollationElementIterator* prefixIter = collator->createCollationElementIterator(prefix);
UErrorCode err = U_ZERO_ERROR;
// The original code was problematic. Consider this match:
// prefix = "fifty-"
// string = " fifty-7"
// The intent is to match string up to the '7', by matching 'fifty-' at position 1
// in the string. Unfortunately, we were getting a match, and then computing where
// the match terminated by rematching the string. The rematch code was using as an
// initial guess the substring of string between 0 and prefix.length. Because of
// the leading space and trailing hyphen (both ignorable) this was succeeding, leaving
// the position before the hyphen in the string. Recursing down, we then parsed the
// remaining string '-7' as numeric. The resulting number turned out as 43 (50 - 7).
// This was not pretty, especially since the string "fifty-7" parsed just fine.
//
// We have newer APIs now, so we can use calls on the iterator to determine what we
// matched up to. If we terminate because we hit the last element in the string,
// our match terminates at this length. If we terminate because we hit the last element
// in the target, our match terminates at one before the element iterator position.
// match collation elements between the strings
int32_t oStr = strIter->next(err);
int32_t oPrefix = prefixIter->next(err);
while (oPrefix != CollationElementIterator::NULLORDER) {
// skip over ignorable characters in the target string
while (CollationElementIterator::primaryOrder(oStr) == 0
&& oStr != CollationElementIterator::NULLORDER) {
oStr = strIter->next(err);
}
// skip over ignorable characters in the prefix
while (CollationElementIterator::primaryOrder(oPrefix) == 0
&& oPrefix != CollationElementIterator::NULLORDER) {
oPrefix = prefixIter->next(err);
}
// dlf: move this above following test, if we consume the
// entire target, aren't we ok even if the source was also
// entirely consumed?
// if skipping over ignorables brought to the end of
// the prefix, we DID match: drop out of the loop
if (oPrefix == CollationElementIterator::NULLORDER) {
break;
}
// if skipping over ignorables brought us to the end
// of the target string, we didn't match and return 0
if (oStr == CollationElementIterator::NULLORDER) {
delete prefixIter;
delete strIter;
return 0;
}
// match collation elements from the two strings
// (considering only primary differences). If we
// get a mismatch, dump out and return 0
if (CollationElementIterator::primaryOrder(oStr)
!= CollationElementIterator::primaryOrder(oPrefix)) {
delete prefixIter;
delete strIter;
return 0;
// otherwise, advance to the next character in each string
// and loop (we drop out of the loop when we exhaust
// collation elements in the prefix)
} else {
oStr = strIter->next(err);
oPrefix = prefixIter->next(err);
}
}
int32_t result = strIter->getOffset();
if (oStr != CollationElementIterator::NULLORDER) {
--result; // back over character that we don't want to consume;
}
#ifdef RBNF_DEBUG
fprintf(stderr, "prefix length: %d\n", result);
#endif
delete prefixIter;
delete strIter;
return result;
#if 0
//----------------------------------------------------------------
// JDK 1.2-specific API call
// return strIter.getOffset();
//----------------------------------------------------------------
// JDK 1.1 HACK (take out for 1.2-specific code)
// if we make it to here, we have a successful match. Now we
// have to find out HOW MANY characters from the target string
// matched the prefix (there isn't necessarily a one-to-one
// mapping between collation elements and characters).
// In JDK 1.2, there's a simple getOffset() call we can use.
// In JDK 1.1, on the other hand, we have to go through some
// ugly contortions. First, use the collator to compare the
// same number of characters from the prefix and target string.
// If they're equal, we're done.
collator->setStrength(Collator::PRIMARY);
if (str.length() >= prefix.length()) {
UnicodeString temp;
temp.setTo(str, 0, prefix.length());
if (collator->equals(temp, prefix)) {
#ifdef RBNF_DEBUG
fprintf(stderr, "returning: %d\n", prefix.length());
#endif
return prefix.length();
}
}
// if they're not equal, then we have to compare successively
// larger and larger substrings of the target string until we
// get to one that matches the prefix. At that point, we know
// how many characters matched the prefix, and we can return.
int32_t p = 1;
while (p <= str.length()) {
UnicodeString temp;
temp.setTo(str, 0, p);
if (collator->equals(temp, prefix)) {
return p;
} else {
++p;
}
}
// SHOULD NEVER GET HERE!!!
return 0;
//----------------------------------------------------------------
#endif
// If lenient parsing is turned off, forget all that crap above.
// Just use String.startsWith() and be done with it.
} else
#endif
{
if (str.startsWith(prefix)) {
return prefix.length();
} else {
return 0;
}
}
}
/**
* Searches a string for another string. If lenient parsing is off,
* this just calls indexOf(). If lenient parsing is on, this function
* uses CollationElementIterator to match characters, and only
* primary-order differences are significant in determining whether
* there's a match.
* @param str The string to search
* @param key The string to search "str" for
* @param startingAt The index into "str" where the search is to
* begin
* @return A two-element array of ints. Element 0 is the position
* of the match, or -1 if there was no match. Element 1 is the
* number of characters in "str" that matched (which isn't necessarily
* the same as the length of "key")
*/
int32_t
NFRule::findText(const UnicodeString& str,
const UnicodeString& key,
int32_t startingAt,
int32_t* length) const
{
#if !UCONFIG_NO_COLLATION
// if lenient parsing is turned off, this is easy: just call
// String.indexOf() and we're done
if (!formatter->isLenient()) {
*length = key.length();
return str.indexOf(key, startingAt);
// but if lenient parsing is turned ON, we've got some work
// ahead of us
} else
#endif
{
//----------------------------------------------------------------
// JDK 1.1 HACK (take out of 1.2-specific code)
// in JDK 1.2, CollationElementIterator provides us with an
// API to map between character offsets and collation elements
// and we can do this by marching through the string comparing
// collation elements. We can't do that in JDK 1.1. Insted,
// we have to go through this horrible slow mess:
int32_t p = startingAt;
int32_t keyLen = 0;
// basically just isolate smaller and smaller substrings of
// the target string (each running to the end of the string,
// and with the first one running from startingAt to the end)
// and then use prefixLength() to see if the search key is at
// the beginning of each substring. This is excruciatingly
// slow, but it will locate the key and tell use how long the
// matching text was.
UnicodeString temp;
while (p < str.length() && keyLen == 0) {
temp.setTo(str, p, str.length() - p);
keyLen = prefixLength(temp, key);
if (keyLen != 0) {
*length = keyLen;
return p;
}
++p;
}
// if we make it to here, we didn't find it. Return -1 for the
// location. The length should be ignored, but set it to 0,
// which should be "safe"
*length = 0;
return -1;
//----------------------------------------------------------------
// JDK 1.2 version of this routine
//RuleBasedCollator collator = (RuleBasedCollator)formatter.getCollator();
//
//CollationElementIterator strIter = collator.getCollationElementIterator(str);
//CollationElementIterator keyIter = collator.getCollationElementIterator(key);
//
//int keyStart = -1;
//
//str.setOffset(startingAt);
//
//int oStr = strIter.next();
//int oKey = keyIter.next();
//while (oKey != CollationElementIterator.NULLORDER) {
// while (oStr != CollationElementIterator.NULLORDER &&
// CollationElementIterator.primaryOrder(oStr) == 0)
// oStr = strIter.next();
//
// while (oKey != CollationElementIterator.NULLORDER &&
// CollationElementIterator.primaryOrder(oKey) == 0)
// oKey = keyIter.next();
//
// if (oStr == CollationElementIterator.NULLORDER) {
// return new int[] { -1, 0 };
// }
//
// if (oKey == CollationElementIterator.NULLORDER) {
// break;
// }
//
// if (CollationElementIterator.primaryOrder(oStr) ==
// CollationElementIterator.primaryOrder(oKey)) {
// keyStart = strIter.getOffset();
// oStr = strIter.next();
// oKey = keyIter.next();
// } else {
// if (keyStart != -1) {
// keyStart = -1;
// keyIter.reset();
// } else {
// oStr = strIter.next();
// }
// }
//}
//
//if (oKey == CollationElementIterator.NULLORDER) {
// return new int[] { keyStart, strIter.getOffset() - keyStart };
//} else {
// return new int[] { -1, 0 };
//}
}
}
/**
* Checks to see whether a string consists entirely of ignorable
* characters.
* @param str The string to test.
* @return true if the string is empty of consists entirely of
* characters that the number formatter's collator says are
* ignorable at the primary-order level. false otherwise.
*/
UBool
NFRule::allIgnorable(const UnicodeString& str) const
{
// if the string is empty, we can just return true
if (str.length() == 0) {
return TRUE;
}
#if !UCONFIG_NO_COLLATION
// if lenient parsing is turned on, walk through the string with
// a collation element iterator and make sure each collation
// element is 0 (ignorable) at the primary level
if (formatter->isLenient()) {
RuleBasedCollator* collator = (RuleBasedCollator*)(formatter->getCollator());
CollationElementIterator* iter = collator->createCollationElementIterator(str);
UErrorCode err = U_ZERO_ERROR;
int32_t o = iter->next(err);
while (o != CollationElementIterator::NULLORDER
&& CollationElementIterator::primaryOrder(o) == 0) {
o = iter->next(err);
}
delete iter;
return o == CollationElementIterator::NULLORDER;
}
#endif
// if lenient parsing is turned off, there is no such thing as
// an ignorable character: return true only if the string is empty
return FALSE;
}
U_NAMESPACE_END
/* U_HAVE_RBNF */
#endif