883 lines
31 KiB
C++
883 lines
31 KiB
C++
/*
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**********************************************************************
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* Copyright (C) 1999, International Business Machines
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* Corporation and others. All Rights Reserved.
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**********************************************************************
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* Date Name Description
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* 11/17/99 aliu Creation.
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**********************************************************************
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*/
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#include "rbt_pars.h"
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#include "unicode/rbt.h"
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#include "rbt_rule.h"
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#include "unirange.h"
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#include "rbt_data.h"
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#include "unicode/uniset.h"
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#include "cstring.h"
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#include "unicode/parsepos.h"
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#include "symtable.h"
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#include "unicode/parseerr.h"
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#include "hash.h"
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#include "unicode/unicode.h"
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#include "unicode/putil.h"
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// Operators
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#define VARIABLE_DEF_OP ((UChar)0x003D) /*=*/
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#define FORWARD_RULE_OP ((UChar)0x003E) /*>*/
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#define REVERSE_RULE_OP ((UChar)0x003C) /*<*/
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#define FWDREV_RULE_OP ((UChar)0x007E) /*~*/ // internal rep of <> op
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#define OPERATORS UNICODE_STRING("=><", 3)
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// Other special characters
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#define QUOTE ((UChar)0x0027) /*'*/
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#define ESCAPE ((UChar)0x005C) /*\*/
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#define END_OF_RULE ((UChar)0x003B) /*;*/
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#define RULE_COMMENT_CHAR ((UChar)0x0023) /*#*/
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#define SEGMENT_OPEN ((UChar)0x0028) /*(*/
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#define SEGMENT_CLOSE ((UChar)0x0029) /*)*/
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#define CONTEXT_ANTE ((UChar)0x007B) /*{*/
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#define CONTEXT_POST ((UChar)0x007D) /*}*/
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#define SET_OPEN ((UChar)0x005B) /*[*/
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#define SET_CLOSE ((UChar)0x005D) /*]*/
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#define CURSOR_POS ((UChar)0x007C) /*|*/
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#define CURSOR_OFFSET ((UChar)0x0040) /*@*/
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#define ANCHOR_START ((UChar)0x005E) /*^*/
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// By definition, the ANCHOR_END special character is a
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// trailing SymbolTable.SYMBOL_REF character.
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// private static final char ANCHOR_END = '$';
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const UnicodeString TransliterationRuleParser::gOPERATORS = OPERATORS;
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//----------------------------------------------------------------------
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// BEGIN ParseData
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//----------------------------------------------------------------------
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/**
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* This class implements the SymbolTable interface. It is used
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* during parsing to give UnicodeSet access to variables that
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* have been defined so far. Note that it uses setVariablesVector,
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* _not_ data.setVariables.
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*/
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class ParseData : public SymbolTable {
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public:
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const TransliterationRuleData* data; // alias
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const UVector* setVariablesVector; // alias
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ParseData(const TransliterationRuleData* data = 0,
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const UVector* setVariablesVector = 0);
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virtual const UnicodeString* lookup(const UnicodeString& s) const;
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virtual const UnicodeSet* lookupSet(UChar ch) const;
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virtual UnicodeString parseReference(const UnicodeString& text,
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ParsePosition& pos, int32_t limit) const;
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};
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ParseData::ParseData(const TransliterationRuleData* d,
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const UVector* sets) :
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data(d), setVariablesVector(sets) {}
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/**
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* Implement SymbolTable API.
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*/
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const UnicodeString* ParseData::lookup(const UnicodeString& name) const {
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return (const UnicodeString*) data->variableNames->get(name);
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}
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/**
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* Implement SymbolTable API.
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*/
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const UnicodeSet* ParseData::lookupSet(UChar ch) const {
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// Note that we cannot use data.lookupSet() because the
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// set array has not been constructed yet.
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const UnicodeSet* set = NULL;
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int32_t i = ch - data->setVariablesBase;
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if (i >= 0 && i < setVariablesVector->size()) {
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int32_t i = ch - data->setVariablesBase;
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set = (i < setVariablesVector->size()) ?
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(UnicodeSet*) setVariablesVector->elementAt(i) : 0;
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}
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return set;
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}
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/**
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* Implement SymbolTable API. Parse out a symbol reference
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* name.
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*/
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UnicodeString ParseData::parseReference(const UnicodeString& text,
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ParsePosition& pos, int32_t limit) const {
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int32_t start = pos.getIndex();
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int32_t i = start;
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UnicodeString result;
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while (i < limit) {
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UChar c = text.charAt(i);
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if ((i==start && !Unicode::isUnicodeIdentifierStart(c)) ||
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!Unicode::isUnicodeIdentifierPart(c)) {
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break;
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}
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++i;
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}
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if (i == start) { // No valid name chars
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return result; // Indicate failure with empty string
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}
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pos.setIndex(i);
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text.extractBetween(start, i, result);
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return result;
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}
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//----------------------------------------------------------------------
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// BEGIN RuleHalf
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//----------------------------------------------------------------------
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/**
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* A class representing one side of a rule. This class knows how to
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* parse half of a rule. It is tightly coupled to the method
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* RuleBasedTransliterator.Parser.parseRule().
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*/
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class RuleHalf {
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public:
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UnicodeString text;
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int32_t cursor; // position of cursor in text
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int32_t ante; // position of ante context marker '{' in text
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int32_t post; // position of post context marker '}' in text
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// Record the position of the segment substrings and references. A
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// given side should have segments or segment references, but not
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// both.
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UVector* segments; // ref substring start,limits
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int32_t maxRef; // index of largest ref (1..9)
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// Record the offset to the cursor either to the left or to the
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// right of the key. This is indicated by characters on the output
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// side that allow the cursor to be positioned arbitrarily within
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// the matching text. For example, abc{def} > | @@@ xyz; changes
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// def to xyz and moves the cursor to before abc. Offset characters
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// must be at the start or end, and they cannot move the cursor past
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// the ante- or postcontext text. Placeholders are only valid in
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// output text.
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int32_t cursorOffset; // only nonzero on output side
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UBool anchorStart;
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UBool anchorEnd;
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TransliterationRuleParser& parser;
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static const UnicodeString gOperators;
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//--------------------------------------------------
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// Methods
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RuleHalf(TransliterationRuleParser& parser);
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~RuleHalf();
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/**
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* Parse one side of a rule, stopping at either the limit,
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* the END_OF_RULE character, or an operator. Return
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* the pos of the terminating character (or limit).
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*/
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int32_t parse(const UnicodeString& rule, int32_t pos, int32_t limit);
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/**
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* Remove context.
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*/
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void removeContext();
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/**
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* Create and return an int[] array of segments.
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*/
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int32_t* createSegments() const;
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int syntaxError(int32_t code,
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const UnicodeString& rule,
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int32_t start) {
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return parser.syntaxError(code, rule, start);
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}
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private:
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// Disallowed methods; no impl.
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RuleHalf(const RuleHalf&);
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RuleHalf& operator=(const RuleHalf&);
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};
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// Store int32_t as a void* in a UVector. DO NOT ASSUME sizeof(void*)
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// is 32. Assume sizeof(void*) >= 32.
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inline void* _int32_to_voidPtr(int32_t x) {
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void* a = 0; // May be > 32 bits
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*(int32_t*)&a = x; // Careful here...
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return a;
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}
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inline int32_t _voidPtr_to_int32(void* x) {
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void* a = x; // Copy to stack (portability)
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return *(int32_t*)&a; // Careful here...
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}
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const UnicodeString RuleHalf::gOperators = OPERATORS;
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RuleHalf::RuleHalf(TransliterationRuleParser& p) : parser(p) {
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cursor = -1;
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ante = -1;
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post = -1;
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segments = NULL;
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maxRef = -1;
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cursorOffset = 0;
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anchorStart = anchorEnd = FALSE;
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}
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RuleHalf::~RuleHalf() {
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delete segments;
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}
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/**
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* Parse one side of a rule, stopping at either the limit,
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* the END_OF_RULE character, or an operator. Return
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* the pos of the terminating character (or limit).
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*/
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int32_t RuleHalf::parse(const UnicodeString& rule, int32_t pos, int32_t limit) {
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int32_t start = pos;
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UnicodeString& buf = text;
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ParsePosition pp;
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int32_t cursorOffsetPos = 0; // Position of first CURSOR_OFFSET on _right_
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UnicodeString scratch;
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bool_t done = FALSE;
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while (pos < limit && !done) {
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UChar c = rule.charAt(pos++);
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if (Unicode::isWhitespace(c)) {
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// Ignore whitespace. Note that this is not Unicode
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// spaces, but Java spaces -- a subset, representing
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// whitespace likely to be seen in code.
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continue;
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}
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if (gOperators.indexOf(c) >= 0) {
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--pos; // Backup to point to operator
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break;
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}
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if (anchorEnd) {
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// Text after a presumed end anchor is a syntax err
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return syntaxError(RuleBasedTransliterator::MALFORMED_VARIABLE_REFERENCE, rule, start);
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}
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// Handle escapes
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if (c == ESCAPE) {
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if (pos == limit) {
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return syntaxError(RuleBasedTransliterator::TRAILING_BACKSLASH, rule, start);
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}
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UChar32 escaped = rule.unescapeAt(pos); // pos is already past '\\'
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if (escaped == (UChar32) -1) {
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return syntaxError(RuleBasedTransliterator::MALFORMED_UNICODE_ESCAPE, rule, start);
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}
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buf.append((UChar) escaped);
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continue;
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}
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// Handle quoted matter
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if (c == QUOTE) {
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int32_t iq = rule.indexOf(QUOTE, pos);
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if (iq == pos) {
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buf.append(c); // Parse [''] outside quotes as [']
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++pos;
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} else {
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/* This loop picks up a segment of quoted text of the
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* form 'aaaa' each time through. If this segment
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* hasn't really ended ('aaaa''bbbb') then it keeps
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* looping, each time adding on a new segment. When it
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* reaches the final quote it breaks.
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*/
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for (;;) {
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if (iq < 0) {
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return syntaxError(RuleBasedTransliterator::UNTERMINATED_QUOTE, rule, start);
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}
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scratch.truncate(0);
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rule.extractBetween(pos, iq, scratch);
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buf.append(scratch);
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pos = iq+1;
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if (pos < limit && rule.charAt(pos) == QUOTE) {
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// Parse [''] inside quotes as [']
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iq = rule.indexOf(QUOTE, pos+1);
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// Continue looping
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} else {
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break;
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}
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}
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}
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continue;
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}
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switch (c) {
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case ANCHOR_START:
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if (buf.length() == 0 && !anchorStart) {
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anchorStart = TRUE;
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} else {
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return syntaxError(RuleBasedTransliterator::MISPLACED_ANCHOR_START,
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rule, start);
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}
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break;
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case SEGMENT_OPEN:
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case SEGMENT_CLOSE:
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// Handle segment definitions "(" and ")"
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// Parse "(", ")"
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if (segments == NULL) {
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segments = new UVector();
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}
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if ((c == SEGMENT_OPEN) !=
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(segments->size() % 2 == 0)) {
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return syntaxError(RuleBasedTransliterator::MISMATCHED_SEGMENT_DELIMITERS,
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rule, start);
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}
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segments->addElement(_int32_to_voidPtr(buf.length()));
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break;
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case END_OF_RULE:
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--pos; // Backup to point to END_OF_RULE
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done = TRUE;
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break;
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case SymbolTable::SYMBOL_REF:
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// Handle variable references and segment references "$1" .. "$9"
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{
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// A variable reference must be followed immediately
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// by a Unicode identifier start and zero or more
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// Unicode identifier part characters, or by a digit
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// 1..9 if it is a segment reference.
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if (pos == limit) {
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// A variable ref character at the end acts as
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// an anchor to the context limit, as in perl.
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anchorEnd = TRUE;
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break;
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}
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// Parse "$1" "$2" .. "$9"
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c = rule.charAt(pos);
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int32_t r = Unicode::digit(c, 10);
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if (r >= 1 && r <= 9) {
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if (r > maxRef) {
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maxRef = r;
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}
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buf.append(parser.data->getSegmentStandin(r));
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++pos;
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} else {
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pp.setIndex(pos);
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UnicodeString name = parser.parseData->
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parseReference(rule, pp, limit);
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if (name.length() == 0) {
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// This means the '$' was not followed by a
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// valid name. Try to interpret it as an
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// end anchor then. If this also doesn't work
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// (if we see a following character) then signal
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// an error.
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anchorEnd = TRUE;
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break;
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}
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pos = pp.getIndex();
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// If this is a variable definition statement,
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// then the LHS variable will be undefined. In
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// that case appendVariableDef() will append the
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// special placeholder char variableLimit-1.
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parser.appendVariableDef(name, buf);
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}
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}
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break;
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case CONTEXT_ANTE:
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if (ante >= 0) {
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return syntaxError(RuleBasedTransliterator::MULTIPLE_ANTE_CONTEXTS, rule, start);
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}
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ante = buf.length();
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break;
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case CONTEXT_POST:
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if (post >= 0) {
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return syntaxError(RuleBasedTransliterator::MULTIPLE_POST_CONTEXTS, rule, start);
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}
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post = buf.length();
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break;
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case SET_OPEN:
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pp.setIndex(pos-1); // Backup to opening '['
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buf.append(parser.parseSet(rule, pp));
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if (U_FAILURE(parser.status)) {
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return syntaxError(RuleBasedTransliterator::MALFORMED_SET, rule, start);
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}
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pos = pp.getIndex();
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break;
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case CURSOR_POS:
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if (cursor >= 0) {
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return syntaxError(RuleBasedTransliterator::MULTIPLE_CURSORS, rule, start);
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}
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cursor = buf.length();
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break;
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case CURSOR_OFFSET:
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if (cursorOffset < 0) {
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if (buf.length() > 0) {
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return syntaxError(RuleBasedTransliterator::MISPLACED_CURSOR_OFFSET, rule, start);
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}
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--cursorOffset;
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} else if (cursorOffset > 0) {
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if (buf.length() != cursorOffsetPos || cursor >= 0) {
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return syntaxError(RuleBasedTransliterator::MISPLACED_CURSOR_OFFSET, rule, start);
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}
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++cursorOffset;
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} else {
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if (cursor == 0 && buf.length() == 0) {
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cursorOffset = -1;
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} else if (cursor < 0) {
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cursorOffsetPos = buf.length();
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cursorOffset = 1;
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} else {
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return syntaxError(RuleBasedTransliterator::MISPLACED_CURSOR_OFFSET, rule, start);
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}
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}
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break;
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// case SET_CLOSE:
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default:
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// Disallow unquoted characters other than [0-9A-Za-z]
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// in the printable ASCII range. These characters are
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// reserved for possible future use.
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if (c >= 0x0021 && c <= 0x007E &&
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!((c >= 0x0030/*'0'*/ && c <= 0x0039/*'9'*/) ||
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(c >= 0x0041/*'A'*/ && c <= 0x005A/*'Z'*/) ||
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(c >= 0x0061/*'a'*/ && c <= 0x007A/*'z'*/))) {
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return syntaxError(RuleBasedTransliterator::UNQUOTED_SPECIAL, rule, start);
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}
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buf.append(c);
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break;
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}
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}
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if (cursorOffset > 0 && cursor != cursorOffsetPos) {
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return syntaxError(RuleBasedTransliterator::MISPLACED_CURSOR_OFFSET, rule, start);
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}
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// text = buf.toString();
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return pos;
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}
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/**
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* Remove context.
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*/
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void RuleHalf::removeContext() {
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//text = text.substring(ante < 0 ? 0 : ante,
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// post < 0 ? text.length() : post);
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if (post >= 0) {
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text.remove(post);
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}
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if (ante >= 0) {
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text.removeBetween(0, ante);
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}
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ante = post = -1;
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anchorStart = anchorEnd = FALSE;
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}
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/**
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* Create and return an int32_t[] array of segments.
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*/
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int32_t* RuleHalf::createSegments() const {
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if (segments == NULL) {
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return NULL;
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}
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int32_t len = segments->size();
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int32_t* result = new int32_t[len + 1];
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for (int32_t i=0; i<len; ++i) {
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result[i] = _voidPtr_to_int32(segments->elementAt(i));
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}
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result[len] = -1; // end marker
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return result;
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}
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//----------------------------------------------------------------------
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// END RuleHalf
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//----------------------------------------------------------------------
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TransliterationRuleData*
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TransliterationRuleParser::parse(const UnicodeString& rules,
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UTransDirection direction,
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UParseError* parseError) {
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TransliterationRuleParser parser(rules, direction, parseError);
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parser.parseRules();
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if (U_FAILURE(parser.status)) {
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delete parser.data;
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parser.data = 0;
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}
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return parser.data;
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}
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/**
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* @param rules list of rules, separated by newline characters
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* @exception IllegalArgumentException if there is a syntax error in the
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* rules
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*/
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TransliterationRuleParser::TransliterationRuleParser(
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const UnicodeString& theRules,
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UTransDirection theDirection,
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UParseError* theParseError) :
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rules(theRules), direction(theDirection), data(0), parseError(theParseError) {
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parseData = new ParseData(0, &setVariablesVector);
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}
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/**
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* Destructor.
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*/
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TransliterationRuleParser::~TransliterationRuleParser() {
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delete parseData;
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}
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/**
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* Parse the given string as a sequence of rules, separated by newline
|
|
* characters ('\n'), and cause this object to implement those rules. Any
|
|
* previous rules are discarded. Typically this method is called exactly
|
|
* once, during construction.
|
|
* @exception IllegalArgumentException if there is a syntax error in the
|
|
* rules
|
|
*/
|
|
void TransliterationRuleParser::parseRules(void) {
|
|
status = U_ZERO_ERROR;
|
|
|
|
delete data;
|
|
data = new TransliterationRuleData(status);
|
|
if (U_FAILURE(status)) {
|
|
return;
|
|
}
|
|
|
|
parseData->data = data;
|
|
setVariablesVector.removeAllElements();
|
|
if (parseError != 0) {
|
|
parseError->code = 0;
|
|
}
|
|
determineVariableRange();
|
|
|
|
int32_t pos = 0;
|
|
int32_t limit = rules.length();
|
|
while (pos < limit && U_SUCCESS(status)) {
|
|
UChar c = rules.charAt(pos++);
|
|
if (Unicode::isWhitespace(c)) {
|
|
// Ignore leading whitespace. Note that this is not
|
|
// Unicode spaces, but Java spaces -- a subset,
|
|
// representing whitespace likely to be seen in code.
|
|
continue;
|
|
}
|
|
// Skip lines starting with the comment character
|
|
if (c == RULE_COMMENT_CHAR) {
|
|
pos = rules.indexOf((UChar)0x000A /*\n*/, pos) + 1;
|
|
if (pos == 0) {
|
|
break; // No "\n" found; rest of rule is a commnet
|
|
}
|
|
continue; // Either fall out or restart with next line
|
|
}
|
|
// We've found the start of a rule. c is its first
|
|
// character, and pos points past c. Lexically parse the
|
|
// rule into component pieces.
|
|
pos = parseRule(--pos, limit);
|
|
}
|
|
|
|
// Convert the set vector to an array
|
|
data->setVariablesLength = setVariablesVector.size();
|
|
data->setVariables = data->setVariablesLength == 0 ? 0 : new UnicodeSet*[data->setVariablesLength];
|
|
// orphanElement removes the given element and shifts all other
|
|
// elements down. For performance (and code clarity) we work from
|
|
// the end back to index 0.
|
|
for (int32_t i=data->setVariablesLength; i>0; ) {
|
|
--i;
|
|
data->setVariables[i] =
|
|
(UnicodeSet*) setVariablesVector.orphanElementAt(i);
|
|
}
|
|
|
|
// Index the rules
|
|
if (U_SUCCESS(status)) {
|
|
data->ruleSet.freeze(*data, status);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* MAIN PARSER. Parse the next rule in the given rule string, starting
|
|
* at pos. Return the index after the last character parsed. Do not
|
|
* parse characters at or after limit.
|
|
*
|
|
* Important: The character at pos must be a non-whitespace character
|
|
* that is not the comment character.
|
|
*
|
|
* This method handles quoting, escaping, and whitespace removal. It
|
|
* parses the end-of-rule character. It recognizes context and cursor
|
|
* indicators. Once it does a lexical breakdown of the rule at pos, it
|
|
* creates a rule object and adds it to our rule list.
|
|
*/
|
|
int32_t TransliterationRuleParser::parseRule(int32_t pos, int32_t limit) {
|
|
// Locate the left side, operator, and right side
|
|
int32_t start = pos;
|
|
UChar op = 0;
|
|
const UnicodeString& rule = rules; // TEMPORARY: FIX LATER
|
|
|
|
// Use pointers to automatics to make swapping possible.
|
|
RuleHalf _left(*this), _right(*this);
|
|
RuleHalf* left = &_left;
|
|
RuleHalf* right = &_right;
|
|
|
|
undefinedVariableName.remove();
|
|
pos = left->parse(rule, pos, limit);
|
|
if (U_FAILURE(status)) {
|
|
return start;
|
|
}
|
|
|
|
if (pos == limit ||
|
|
gOPERATORS.indexOf(op = rule.charAt(pos++)) < 0) {
|
|
return syntaxError(RuleBasedTransliterator::MISSING_OPERATOR, rule, start);
|
|
}
|
|
|
|
// Found an operator char. Check for forward-reverse operator.
|
|
if (op == REVERSE_RULE_OP &&
|
|
(pos < limit && rule.charAt(pos) == FORWARD_RULE_OP)) {
|
|
++pos;
|
|
op = FWDREV_RULE_OP;
|
|
}
|
|
|
|
pos = right->parse(rule, pos, limit);
|
|
if (U_FAILURE(status)) {
|
|
return start;
|
|
}
|
|
|
|
if (pos < limit) {
|
|
if (rule.charAt(pos) == END_OF_RULE) {
|
|
++pos;
|
|
} else {
|
|
// RuleHalf parser must have terminated at an operator
|
|
return syntaxError(RuleBasedTransliterator::UNQUOTED_SPECIAL, rule, start);
|
|
}
|
|
}
|
|
|
|
if (op == VARIABLE_DEF_OP) {
|
|
// LHS is the name. RHS is a single character, either a literal
|
|
// or a set (already parsed). If RHS is longer than one
|
|
// character, it is either a multi-character string, or multiple
|
|
// sets, or a mixture of chars and sets -- syntax error.
|
|
|
|
// We expect to see a single undefined variable (the one being
|
|
// defined).
|
|
if (undefinedVariableName.length() == 0) {
|
|
// "Missing '$' or duplicate definition"
|
|
return syntaxError(RuleBasedTransliterator::BAD_VARIABLE_DEFINITION, rule, start);
|
|
}
|
|
if (left->text.length() != 1 || left->text.charAt(0) != variableLimit) {
|
|
// "Malformed LHS"
|
|
return syntaxError(RuleBasedTransliterator::MALFORMED_VARIABLE_DEFINITION, rule, start);
|
|
}
|
|
if (left->anchorStart || left->anchorEnd ||
|
|
right->anchorStart || right->anchorEnd) {
|
|
return syntaxError(RuleBasedTransliterator::MALFORMED_VARIABLE_DEFINITION, rule, start);
|
|
}
|
|
// We allow anything on the right, including an empty string.
|
|
UnicodeString* value = new UnicodeString(right->text);
|
|
data->variableNames->put(undefinedVariableName, value, status);
|
|
|
|
++variableLimit;
|
|
return pos;
|
|
}
|
|
|
|
// If this is not a variable definition rule, we shouldn't have
|
|
// any undefined variable names.
|
|
if (undefinedVariableName.length() != 0) {
|
|
syntaxError(// "Undefined variable $" + undefinedVariableName,
|
|
RuleBasedTransliterator::UNDEFINED_VARIABLE,
|
|
rule, start);
|
|
}
|
|
|
|
// If the direction we want doesn't match the rule
|
|
// direction, do nothing.
|
|
if (op != FWDREV_RULE_OP &&
|
|
((direction == UTRANS_FORWARD) != (op == FORWARD_RULE_OP))) {
|
|
return pos;
|
|
}
|
|
|
|
// Transform the rule into a forward rule by swapping the
|
|
// sides if necessary.
|
|
if (direction == UTRANS_REVERSE) {
|
|
left = &_right;
|
|
right = &_left;
|
|
}
|
|
|
|
// Remove non-applicable elements in forward-reverse
|
|
// rules. Bidirectional rules ignore elements that do not
|
|
// apply.
|
|
if (op == FWDREV_RULE_OP) {
|
|
right->removeContext();
|
|
delete right->segments;
|
|
right->segments = NULL;
|
|
left->cursor = left->maxRef = -1;
|
|
left->cursorOffset = 0;
|
|
}
|
|
|
|
// Normalize context
|
|
if (left->ante < 0) {
|
|
left->ante = 0;
|
|
}
|
|
if (left->post < 0) {
|
|
left->post = left->text.length();
|
|
}
|
|
|
|
// Context is only allowed on the input side. Cursors are only
|
|
// allowed on the output side. Segment delimiters can only appear
|
|
// on the left, and references on the right. Cursor offset
|
|
// cannot appear without an explicit cursor. Cursor offset
|
|
// cannot place the cursor outside the limits of the context.
|
|
// Anchors are only allowed on the input side.
|
|
if (right->ante >= 0 || right->post >= 0 || left->cursor >= 0 ||
|
|
right->segments != NULL || left->maxRef >= 0 ||
|
|
(right->cursorOffset != 0 && right->cursor < 0) ||
|
|
(right->cursorOffset > (left->text.length() - left->post)) ||
|
|
(-right->cursorOffset > left->ante) ||
|
|
right->anchorStart || right->anchorEnd) {
|
|
|
|
return syntaxError(RuleBasedTransliterator::MALFORMED_RULE, rule, start);
|
|
}
|
|
|
|
// Check integrity of segments and segment references. Each
|
|
// segment's start must have a corresponding limit, and the
|
|
// references must not refer to segments that do not exist.
|
|
if (left->segments != NULL) {
|
|
int n = left->segments->size();
|
|
if (n % 2 != 0) {
|
|
return syntaxError(RuleBasedTransliterator::MISSING_SEGMENT_CLOSE, rule, start);
|
|
}
|
|
n /= 2;
|
|
if (right->maxRef > n) {
|
|
return syntaxError(RuleBasedTransliterator::UNDEFINED_SEGMENT_REFERENCE, rule, start);
|
|
}
|
|
}
|
|
|
|
data->ruleSet.addRule(new TransliterationRule(
|
|
left->text, left->ante, left->post,
|
|
right->text, right->cursor, right->cursorOffset,
|
|
left->createSegments(),
|
|
left->anchorStart, left->anchorEnd,
|
|
status), status);
|
|
|
|
return pos;
|
|
}
|
|
|
|
/**
|
|
* Called by main parser upon syntax error. Search the rule string
|
|
* for the probable end of the rule. Of course, if the error is that
|
|
* the end of rule marker is missing, then the rule end will not be found.
|
|
* In any case the rule start will be correctly reported.
|
|
* @param msg error description
|
|
* @param rule pattern string
|
|
* @param start position of first character of current rule
|
|
*/
|
|
int32_t TransliterationRuleParser::syntaxError(int32_t parseErrorCode,
|
|
const UnicodeString& rule,
|
|
int32_t start) {
|
|
if (parseError != 0) {
|
|
parseError->code = parseErrorCode;
|
|
parseError->line = 0; // We don't return a line #
|
|
parseError->offset = start; // Character offset from rule start
|
|
int32_t end = quotedIndexOf(rule, start, rule.length(), END_OF_RULE);
|
|
if (end < 0) {
|
|
end = rule.length();
|
|
}
|
|
int32_t len = uprv_max(end - start, U_PARSE_CONTEXT_LEN-1);
|
|
// Extract everything into the preContext and leave the postContext
|
|
// blank, since we don't have precise error position.
|
|
// TODO: Fix this.
|
|
rule.extract(start, len, parseError->preContext); // Current rule
|
|
parseError->preContext[len] = 0;
|
|
parseError->postContext[0] = 0;
|
|
}
|
|
status = U_ILLEGAL_ARGUMENT_ERROR;
|
|
return start;
|
|
}
|
|
|
|
/**
|
|
* Parse a UnicodeSet out, store it, and return the stand-in character
|
|
* used to represent it.
|
|
*/
|
|
UChar TransliterationRuleParser::parseSet(const UnicodeString& rule,
|
|
ParsePosition& pos) {
|
|
UnicodeSet* set = new UnicodeSet(rule, pos, *parseData, status);
|
|
if (variableNext >= variableLimit) {
|
|
// throw new RuntimeException("Private use variables exhausted");
|
|
delete set;
|
|
status = U_ILLEGAL_ARGUMENT_ERROR;
|
|
return 0;
|
|
}
|
|
set->compact();
|
|
setVariablesVector.addElement(set);
|
|
return variableNext++;
|
|
}
|
|
|
|
/**
|
|
* Append the value of the given variable name to the given
|
|
* UnicodeString.
|
|
*/
|
|
void TransliterationRuleParser::appendVariableDef(const UnicodeString& name,
|
|
UnicodeString& buf) {
|
|
const UnicodeString* s = (const UnicodeString*) data->variableNames->get(name);
|
|
if (s == NULL) {
|
|
// We allow one undefined variable so that variable definition
|
|
// statements work. For the first undefined variable we return
|
|
// the special placeholder variableLimit-1, and save the variable
|
|
// name.
|
|
if (undefinedVariableName.length() == 0) {
|
|
undefinedVariableName = name;
|
|
if (variableNext >= variableLimit) {
|
|
// throw new RuntimeException("Private use variables exhausted");
|
|
status = U_ILLEGAL_ARGUMENT_ERROR;
|
|
return;
|
|
}
|
|
buf.append((UChar) --variableLimit);
|
|
} else {
|
|
//throw new IllegalArgumentException("Undefined variable $"
|
|
// + name);
|
|
status = U_ILLEGAL_ARGUMENT_ERROR;
|
|
return;
|
|
}
|
|
} else {
|
|
buf.append(*s);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Determines what part of the private use region of Unicode we can use for
|
|
* variable stand-ins. The correct way to do this is as follows: Parse each
|
|
* rule, and for forward and reverse rules, take the FROM expression, and
|
|
* make a hash of all characters used. The TO expression should be ignored.
|
|
* When done, everything not in the hash is available for use. In practice,
|
|
* this method may employ some other algorithm for improved speed.
|
|
*/
|
|
void TransliterationRuleParser::determineVariableRange(void) {
|
|
UnicodeRange privateUse(0xE000, 0x1900); // Private use area
|
|
|
|
UnicodeRange* r = privateUse.largestUnusedSubrange(rules);
|
|
|
|
data->setVariablesBase = variableNext = variableLimit = (UChar) 0;
|
|
|
|
if (r != 0) {
|
|
// Allocate 9 characters for segment references 1 through 9
|
|
data->segmentBase = r->start;
|
|
data->setVariablesBase = variableNext = (UChar) (data->segmentBase + 9);
|
|
variableLimit = (UChar) (r->start + r->length);
|
|
delete r;
|
|
}
|
|
|
|
if (variableNext >= variableLimit) {
|
|
status = U_ILLEGAL_ARGUMENT_ERROR;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Returns the index of a character, ignoring quoted text.
|
|
* For example, in the string "abc'hide'h", the 'h' in "hide" will not be
|
|
* found by a search for 'h'.
|
|
*/
|
|
int32_t TransliterationRuleParser::quotedIndexOf(const UnicodeString& text,
|
|
int32_t start, int32_t limit,
|
|
UChar charToFind) {
|
|
for (int32_t i=start; i<limit; ++i) {
|
|
UChar c = text.charAt(i);
|
|
if (c == ESCAPE) {
|
|
++i;
|
|
} else if (c == QUOTE) {
|
|
while (++i < limit
|
|
&& text.charAt(i) != QUOTE) {}
|
|
} else if (c == charToFind) {
|
|
return i;
|
|
}
|
|
}
|
|
return -1;
|
|
}
|