Add m-esr52 at 52.6.0

1 files changed, 1609 insertions, 0 deletions

diff --git a/intl/icu/source/i18n/nfrule.cpp b/intl/icu/source/i18n/nfrule.cpp
new file mode 100644
index 000000000..a188fe11a
--- /dev/null
+++ b/intl/icu/source/i18n/nfrule.cpp
@@ -0,0 +1,1609 @@
+// Copyright (C) 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+/*
+******************************************************************************
+*   Copyright (C) 1997-2015, 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/localpointer.h"
+#include "unicode/rbnf.h"
+#include "unicode/tblcoll.h"
+#include "unicode/plurfmt.h"
+#include "unicode/upluralrules.h"
+#include "unicode/coleitr.h"
+#include "unicode/uchar.h"
+#include "nfrs.h"
+#include "nfrlist.h"
+#include "nfsubs.h"
+#include "patternprops.h"
+
+U_NAMESPACE_BEGIN
+
+NFRule::NFRule(const RuleBasedNumberFormat* _rbnf, const UnicodeString &_ruleText, UErrorCode &status)
+  : baseValue((int32_t)0)
+  , radix(10)
+  , exponent(0)
+  , decimalPoint(0)
+  , ruleText(_ruleText)
+  , sub1(NULL)
+  , sub2(NULL)
+  , formatter(_rbnf)
+  , rulePatternFormat(NULL)
+{
+    if (!ruleText.isEmpty()) {
+        parseRuleDescriptor(ruleText, status);
+    }
+}
+
+NFRule::~NFRule()
+{
+    if (sub1 != sub2) {
+        delete sub2;
+        sub2 = NULL;
+    }
+    delete sub1;
+    sub1 = NULL;
+    delete rulePatternFormat;
+    rulePatternFormat = NULL;
+}
+
+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 gX = 0x0078;
+
+static const UChar gMinusX[] =                  {0x2D, 0x78, 0};    /* "-x" */
+static const UChar gInf[] =                     {0x49, 0x6E, 0x66, 0}; /* "Inf" */
+static const UChar gNaN[] =                     {0x4E, 0x61, 0x4E, 0}; /* "NaN" */
+
+static const UChar gDollarOpenParenthesis[] =   {0x24, 0x28, 0}; /* "$(" */
+static const UChar gClosedParenthesisDollar[] = {0x29, 0x24, 0}; /* ")$" */
+
+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 gGreaterGreaterGreater[] =   {0x3E, 0x3E, 0x3E, 0}; /* ">>>" */
+
+static const UChar * const RULE_PREFIXES[] = {
+    gLessLess, gLessPercent, gLessHash, gLessZero,
+    gGreaterGreater, gGreaterPercent,gGreaterHash, gGreaterZero,
+    gEqualPercent, gEqualHash, gEqualZero, NULL
+};
+
+void
+NFRule::makeRules(UnicodeString& description,
+                  NFRuleSet *owner,
+                  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, description, status);
+    /* test for NULL */
+    if (rule1 == 0) {
+        status = U_MEMORY_ALLOCATION_ERROR;
+        return;
+    }
+    description = rule1->ruleText;
+
+    // check the description to see whether there's text enclosed
+    // in brackets
+    int32_t brack1 = description.indexOf(gLeftBracket);
+    int32_t brack2 = brack1 < 0 ? -1 : 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 (brack2 < 0 || brack1 > brack2
+        || rule1->getType() == kProperFractionRule
+        || rule1->getType() == kNegativeNumberRule
+        || rule1->getType() == kInfinityRule
+        || rule1->getType() == kNaNRule)
+    {
+        rule1->extractSubstitutions(owner, description, predecessor, status);
+    }
+    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, UnicodeString(), status);
+            /* test for NULL */
+            if (rule2 == 0) {
+                status = U_MEMORY_ALLOCATION_ERROR;
+                return;
+            }
+            if (rule1->baseValue >= 0) {
+                rule2->baseValue = rule1->baseValue;
+                if (!owner->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->extractSubstitutions(owner, sbuf, predecessor, 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->extractSubstitutions(owner, sbuf, predecessor, 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) {
+            if (rule2->baseValue >= kNoBase) {
+                rules.add(rule2);
+            }
+            else {
+                owner->setNonNumericalRule(rule2);
+            }
+        }
+    }
+    if (rule1->baseValue >= kNoBase) {
+        rules.add(rule1);
+    }
+    else {
+        owner->setNonNumericalRule(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) {
+        // 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() && PatternProps::isWhiteSpace(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 identifier value
+        int descriptorLength = descriptor.length();
+        UChar firstChar = descriptor.charAt(0);
+        UChar lastChar = descriptor.charAt(descriptorLength - 1);
+        if (firstChar >= gZero && firstChar <= gNine && lastChar != gX) {
+            // 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.
+            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 < descriptorLength) {
+                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 (PatternProps::isWhiteSpace(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 < descriptorLength) {
+                    c = descriptor.charAt(p);
+                    if (c >= gZero && c <= gNine) {
+                        val = val * ll_10 + (int32_t)(c - gZero);
+                    }
+                    else if (c == gGreaterThan) {
+                        break;
+                    }
+                    else if (PatternProps::isWhiteSpace(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;
+                }
+            }
+        }
+        else if (0 == descriptor.compare(gMinusX, 2)) {
+            setType(kNegativeNumberRule);
+        }
+        else if (descriptorLength == 3) {
+            if (firstChar == gZero && lastChar == gX) {
+                setBaseValue(kProperFractionRule, status);
+                decimalPoint = descriptor.charAt(1);
+            }
+            else if (firstChar == gX && lastChar == gX) {
+                setBaseValue(kImproperFractionRule, status);
+                decimalPoint = descriptor.charAt(1);
+            }
+            else if (firstChar == gX && lastChar == gZero) {
+                setBaseValue(kMasterRule, status);
+                decimalPoint = descriptor.charAt(1);
+            }
+            else if (descriptor.compare(gNaN, 3) == 0) {
+                setBaseValue(kNaNRule, status);
+            }
+            else if (descriptor.compare(gInf, 3) == 0) {
+                setBaseValue(kInfinityRule, status);
+            }
+        }
+    }
+    // else use the default base value for now.
+
+    // 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 UnicodeString &ruleText,
+                             const NFRule* predecessor,
+                             UErrorCode& status)
+{
+    if (U_FAILURE(status)) {
+        return;
+    }
+    this->ruleText = ruleText;
+    sub1 = extractSubstitution(ruleSet, predecessor, status);
+    if (sub1 == NULL) {
+        // Small optimization. There is no need to create a redundant NullSubstitution.
+        sub2 = NULL;
+    }
+    else {
+        sub2 = extractSubstitution(ruleSet, predecessor, status);
+    }
+    int32_t pluralRuleStart = this->ruleText.indexOf(gDollarOpenParenthesis, -1, 0);
+    int32_t pluralRuleEnd = (pluralRuleStart >= 0 ? this->ruleText.indexOf(gClosedParenthesisDollar, -1, pluralRuleStart) : -1);
+    if (pluralRuleEnd >= 0) {
+        int32_t endType = this->ruleText.indexOf(gComma, pluralRuleStart);
+        if (endType < 0) {
+            status = U_PARSE_ERROR;
+            return;
+        }
+        UnicodeString type(this->ruleText.tempSubString(pluralRuleStart + 2, endType - pluralRuleStart - 2));
+        UPluralType pluralType;
+        if (type.startsWith(UNICODE_STRING_SIMPLE("cardinal"))) {
+            pluralType = UPLURAL_TYPE_CARDINAL;
+        }
+        else if (type.startsWith(UNICODE_STRING_SIMPLE("ordinal"))) {
+            pluralType = UPLURAL_TYPE_ORDINAL;
+        }
+        else {
+            status = U_ILLEGAL_ARGUMENT_ERROR;
+            return;
+        }
+        rulePatternFormat = formatter->createPluralFormat(pluralType,
+                this->ruleText.tempSubString(endType + 1, pluralRuleEnd - endType - 1), 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,
+                            UErrorCode& status)
+{
+    NFSubstitution* result = NULL;
+
+    // search the rule's rule text for the first two characters of
+    // a substitution token
+    int32_t subStart = indexOfAnyRulePrefix();
+    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 NULL;
+    }
+
+    // special-case the ">>>" token, since searching for the > at the
+    // end will actually find the > in the middle
+    if (ruleText.indexOf(gGreaterGreaterGreater, 3, 0) == 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 NULL;
+    }
+
+    // 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,
+        this->formatter, 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;
+    radix = 10;
+
+    // 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) {
+        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 {
+        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.
+ * @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::indexOfAnyRulePrefix() const
+{
+    int result = -1;
+    for (int i = 0; RULE_PREFIXES[i]; i++) {
+        int32_t pos = ruleText.indexOf(*RULE_PREFIXES[i]);
+        if (pos != -1 && (result == -1 || pos < result)) {
+            result = pos;
+        }
+    }
+    return result;
+}
+
+//-----------------------------------------------------------------------
+// boilerplate
+//-----------------------------------------------------------------------
+
+static UBool
+util_equalSubstitutions(const NFSubstitution* sub1, const NFSubstitution* sub2)
+{
+    if (sub1) {
+        if (sub2) {
+            return *sub1 == *sub2;
+        }
+    } else if (!sub2) {
+        return TRUE;
+    }
+    return FALSE;
+}
+
+/**
+* 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
+        && util_equalSubstitutions(sub1, rhs.sub1)
+        && util_equalSubstitutions(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, 2); break;
+    case kImproperFractionRule: result.append(gX).append(decimalPoint == 0 ? gDot : decimalPoint).append(gX); break;
+    case kProperFractionRule: result.append(gZero).append(decimalPoint == 0 ? gDot : decimalPoint).append(gX); break;
+    case kMasterRule: result.append(gX).append(decimalPoint == 0 ? gDot : decimalPoint).append(gZero); break;
+    case kInfinityRule: result.append(gInf, 3); break;
+    case kNaNRule: result.append(gNaN, 3); 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.charAt(0) == gSpace && (sub1 == NULL || 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;
+    if (sub2 != NULL) {
+        sub2->toString(temp);
+        ruleTextCopy.insert(sub2->getPos(), temp);
+    }
+    if (sub1 != NULL) {
+        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, int32_t recursionCount, UErrorCode& status) 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)
+    int32_t pluralRuleStart = ruleText.length();
+    int32_t lengthOffset = 0;
+    if (!rulePatternFormat) {
+        toInsertInto.insert(pos, ruleText);
+    }
+    else {
+        pluralRuleStart = ruleText.indexOf(gDollarOpenParenthesis, -1, 0);
+        int pluralRuleEnd = ruleText.indexOf(gClosedParenthesisDollar, -1, pluralRuleStart);
+        int initialLength = toInsertInto.length();
+        if (pluralRuleEnd < ruleText.length() - 1) {
+            toInsertInto.insert(pos, ruleText.tempSubString(pluralRuleEnd + 2));
+        }
+        toInsertInto.insert(pos,
+            rulePatternFormat->format((int32_t)(number/uprv_pow(radix, exponent)), status));
+        if (pluralRuleStart > 0) {
+            toInsertInto.insert(pos, ruleText.tempSubString(0, pluralRuleStart));
+        }
+        lengthOffset = ruleText.length() - (toInsertInto.length() - initialLength);
+    }
+
+    if (sub2 != NULL) {
+        sub2->doSubstitution(number, toInsertInto, pos - (sub2->getPos() > pluralRuleStart ? lengthOffset : 0), recursionCount, status);
+    }
+    if (sub1 != NULL) {
+        sub1->doSubstitution(number, toInsertInto, pos - (sub1->getPos() > pluralRuleStart ? lengthOffset : 0), recursionCount, status);
+    }
+}
+
+/**
+* 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, int32_t recursionCount, UErrorCode& status) 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]
+    int32_t pluralRuleStart = ruleText.length();
+    int32_t lengthOffset = 0;
+    if (!rulePatternFormat) {
+        toInsertInto.insert(pos, ruleText);
+    }
+    else {
+        pluralRuleStart = ruleText.indexOf(gDollarOpenParenthesis, -1, 0);
+        int pluralRuleEnd = ruleText.indexOf(gClosedParenthesisDollar, -1, pluralRuleStart);
+        int initialLength = toInsertInto.length();
+        if (pluralRuleEnd < ruleText.length() - 1) {
+            toInsertInto.insert(pos, ruleText.tempSubString(pluralRuleEnd + 2));
+        }
+        double pluralVal = number;
+        if (0 <= pluralVal && pluralVal < 1) {
+            // We're in a fractional rule, and we have to match the NumeratorSubstitution behavior.
+            // 2.3 can become 0.2999999999999998 for the fraction due to rounding errors.
+            pluralVal = uprv_round(pluralVal * uprv_pow(radix, exponent));
+        }
+        else {
+            pluralVal = pluralVal / uprv_pow(radix, exponent);
+        }
+        toInsertInto.insert(pos, rulePatternFormat->format((int32_t)(pluralVal), status));
+        if (pluralRuleStart > 0) {
+            toInsertInto.insert(pos, ruleText.tempSubString(0, pluralRuleStart));
+        }
+        lengthOffset = ruleText.length() - (toInsertInto.length() - initialLength);
+    }
+
+    if (sub2 != NULL) {
+        sub2->doSubstitution(number, toInsertInto, pos - (sub2->getPos() > pluralRuleStart ? lengthOffset : 0), recursionCount, status);
+    }
+    if (sub1 != NULL) {
+        sub1->doSubstitution(number, toInsertInto, pos - (sub1->getPos() > pluralRuleStart ? lengthOffset : 0), recursionCount, status);
+    }
+}
+
+/**
+* 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 != NULL && sub1->isModulusSubstitution()) || (sub2 != NULL && 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];
+  if (buf != NULL) {
+	  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);
+
+    int32_t sub1Pos = sub1 != NULL ? sub1->getPos() : ruleText.length();
+    int32_t sub2Pos = sub2 != NULL ? sub2->getPos() : ruleText.length();
+
+    // 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, sub1Pos);
+
+#ifdef RBNF_DEBUG
+    fprintf(stderr, "doParse %p ", this);
+    {
+        UnicodeString rt;
+        _appendRuleText(rt);
+        dumpUS(stderr, rt);
+    }
+
+    fprintf(stderr, " text: '");
+    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(), sub1Pos);
+#endif
+
+    if (pp.getIndex() == 0 && sub1Pos != 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;
+    }
+    if (baseValue == kInfinityRule) {
+        // If you match this, don't try to perform any calculations on it.
+        parsePosition.setIndex(pp.getIndex());
+        resVal.setDouble(uprv_getInfinity());
+        return TRUE;
+    }
+    if (baseValue == kNaNRule) {
+        // If you match this, don't try to perform any calculations on it.
+        parsePosition.setIndex(pp.getIndex());
+        resVal.setDouble(uprv_getNaN());
+        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, sub1Pos, sub2Pos - sub1Pos);
+        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 == NULL) {
+            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, sub2Pos, ruleText.length() - sub2Pos);
+            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 == NULL) {
+                if (prefixLength + pp.getIndex() + pp2.getIndex() > highWaterMark) {
+                    highWaterMark = prefixLength + pp.getIndex() + pp2.getIndex();
+                    result = partialResult;
+                }
+            }
+            else {
+                // commented out because ParsePosition doesn't have error index in 1.1.x
+                // restored for ICU4C port
+                int32_t temp = pp2.getErrorIndex() + sub1Pos + pp.getIndex();
+                if (temp> parsePosition.getErrorIndex()) {
+                    parsePosition.setErrorIndex(temp);
+                }
+            }
+        }
+        else {
+            // commented out because ParsePosition doesn't have error index in 1.1.x
+            // restored for ICU4C port
+            int32_t temp = sub1Pos + 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 (sub1Pos != sub2Pos
+        && 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 == NULL) {
+        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) {
+    	UErrorCode status = U_ZERO_ERROR;
+        // 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, status);
+        if (U_FAILURE(status)) { // Memory allocation error.
+        	return;
+        }
+        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
+{
+	UErrorCode status = U_ZERO_ERROR;
+    // 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, status)) {
+    	if (U_FAILURE(status)) { //Memory allocation error.
+    		return 0;
+    	}
+        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();
+                }
+                else {
+                    // commented out because ParsePosition doesn't have error index in 1.1.x
+                    // restored for ICU4C port
+                    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 if (sub == NULL) {
+        return _baseValue;
+    }
+    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)) {
+            // 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();
+        }
+        else {
+            // commented out because ParsePosition doesn't have error index in 1.1.x
+            // restored for ICU4C port
+            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, UErrorCode& status) 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.)
+        const RuleBasedCollator* collator = formatter->getCollator();
+        if (collator == NULL) {
+            status = U_MEMORY_ALLOCATION_ERROR;
+            return 0;
+        }
+        LocalPointer<CollationElementIterator> strIter(collator->createCollationElementIterator(str));
+        LocalPointer<CollationElementIterator> prefixIter(collator->createCollationElementIterator(prefix));
+        // Check for memory allocation error.
+        if (strIter.isNull() || prefixIter.isNull()) {
+            status = U_MEMORY_ALLOCATION_ERROR;
+            return 0;
+        }
+
+        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) {
+                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)) {
+                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
+        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 (rulePatternFormat) {
+        Formattable result;
+        FieldPosition position(UNUM_INTEGER_FIELD);
+        position.setBeginIndex(startingAt);
+        rulePatternFormat->parseType(str, this, result, position);
+        int start = position.getBeginIndex();
+        if (start >= 0) {
+            int32_t pluralRuleStart = ruleText.indexOf(gDollarOpenParenthesis, -1, 0);
+            int32_t pluralRuleSuffix = ruleText.indexOf(gClosedParenthesisDollar, -1, pluralRuleStart) + 2;
+            int32_t matchLen = position.getEndIndex() - start;
+            UnicodeString prefix(ruleText.tempSubString(0, pluralRuleStart));
+            UnicodeString suffix(ruleText.tempSubString(pluralRuleSuffix));
+            if (str.compare(start - prefix.length(), prefix.length(), prefix, 0, prefix.length()) == 0
+                    && str.compare(start + matchLen, suffix.length(), suffix, 0, suffix.length()) == 0)
+            {
+                *length = matchLen + prefix.length() + suffix.length();
+                return start - prefix.length();
+            }
+        }
+        *length = 0;
+        return -1;
+    }
+    if (!formatter->isLenient()) {
+        // if lenient parsing is turned off, this is easy: just call
+        // String.indexOf() and we're done
+        *length = key.length();
+        return str.indexOf(key, startingAt);
+    }
+    else {
+        // but if lenient parsing is turned ON, we've got some work
+        // ahead of us
+        return findTextLenient(str, key, startingAt, length);
+    }
+}
+
+int32_t
+NFRule::findTextLenient(const UnicodeString& str,
+                 const UnicodeString& key,
+                 int32_t startingAt,
+                 int32_t* length) const
+{
+    //----------------------------------------------------------------
+    // 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;
+    UErrorCode status = U_ZERO_ERROR;
+    while (p < str.length() && keyLen == 0) {
+        temp.setTo(str, p, str.length() - p);
+        keyLen = prefixLength(temp, key, status);
+        if (U_FAILURE(status)) {
+            break;
+        }
+        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;
+}
+
+/**
+* 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, UErrorCode& status) 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()) {
+        const RuleBasedCollator* collator = formatter->getCollator();
+        if (collator == NULL) {
+            status = U_MEMORY_ALLOCATION_ERROR;
+            return FALSE;
+        }
+        LocalPointer<CollationElementIterator> iter(collator->createCollationElementIterator(str));
+
+        // Memory allocation error check.
+        if (iter.isNull()) {
+            status = U_MEMORY_ALLOCATION_ERROR;
+            return FALSE;
+        }
+
+        UErrorCode err = U_ZERO_ERROR;
+        int32_t o = iter->next(err);
+        while (o != CollationElementIterator::NULLORDER
+            && CollationElementIterator::primaryOrder(o) == 0) {
+            o = iter->next(err);
+        }
+
+        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;
+}
+
+void
+NFRule::setDecimalFormatSymbols(const DecimalFormatSymbols& newSymbols, UErrorCode& status) {
+    if (sub1 != NULL) {
+        sub1->setDecimalFormatSymbols(newSymbols, status);
+    }
+    if (sub2 != NULL) {
+        sub2->setDecimalFormatSymbols(newSymbols, status);
+    }
+}
+
+U_NAMESPACE_END
+
+/* U_HAVE_RBNF */
+#endif