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Diffstat (limited to 'intl/icu/source/i18n/strmatch.h')
| -rw-r--r-- | intl/icu/source/i18n/strmatch.h | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/intl/icu/source/i18n/strmatch.h b/intl/icu/source/i18n/strmatch.h new file mode 100644 index 0000000000..6d2e392e65 --- /dev/null +++ b/intl/icu/source/i18n/strmatch.h @@ -0,0 +1,252 @@ +// © 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/* + * Copyright (C) 2001-2011, International Business Machines Corporation + * and others. All Rights Reserved. + ********************************************************************** + * Date Name Description + * 07/23/01 aliu Creation. + ********************************************************************** + */ +#ifndef STRMATCH_H +#define STRMATCH_H + +#include "unicode/utypes.h" + +#if !UCONFIG_NO_TRANSLITERATION + +#include "unicode/unistr.h" +#include "unicode/unifunct.h" +#include "unicode/unimatch.h" +#include "unicode/unirepl.h" + +U_NAMESPACE_BEGIN + +class TransliterationRuleData; + +/** + * An object that matches a fixed input string, implementing the + * UnicodeMatcher API. This object also implements the + * UnicodeReplacer API, allowing it to emit the matched text as + * output. Since the match text may contain flexible match elements, + * such as UnicodeSets, the emitted text is not the match pattern, but + * instead a substring of the actual matched text. Following + * convention, the output text is the leftmost match seen up to this + * point. + * + * A StringMatcher may represent a segment, in which case it has a + * positive segment number. This affects how the matcher converts + * itself to a pattern but does not otherwise affect its function. + * + * A StringMatcher that is not a segment should not be used as a + * UnicodeReplacer. + */ +class StringMatcher : public UnicodeFunctor, public UnicodeMatcher, public UnicodeReplacer { + + public: + + /** + * Construct a matcher that matches the given pattern string. + * @param string the pattern to be matched, possibly containing + * stand-ins that represent nested UnicodeMatcher objects. + * @param start inclusive start index of text to be replaced + * @param limit exclusive end index of text to be replaced; + * must be greater than or equal to start + * @param segmentNum the segment number from 1..n, or 0 if this is + * not a segment. + * @param data context object mapping stand-ins to + * UnicodeMatcher objects. + */ + StringMatcher(const UnicodeString& string, + int32_t start, + int32_t limit, + int32_t segmentNum, + const TransliterationRuleData& data); + + /** + * Copy constructor + * @param o the object to be copied. + */ + StringMatcher(const StringMatcher& o); + + /** + * Destructor + */ + virtual ~StringMatcher(); + + /** + * Implement UnicodeFunctor + * @return a copy of the object. + */ + virtual StringMatcher* clone() const override; + + /** + * UnicodeFunctor API. Cast 'this' to a UnicodeMatcher* pointer + * and return the pointer. + * @return the UnicodeMatcher point. + */ + virtual UnicodeMatcher* toMatcher() const override; + + /** + * UnicodeFunctor API. Cast 'this' to a UnicodeReplacer* pointer + * and return the pointer. + * @return the UnicodeReplacer pointer. + */ + virtual UnicodeReplacer* toReplacer() const override; + + /** + * Implement UnicodeMatcher + * @param text the text to be matched + * @param offset on input, the index into text at which to begin + * matching. On output, the limit of the matched text. The + * number of matched characters is the output value of offset + * minus the input value. Offset should always point to the + * HIGH SURROGATE (leading code unit) of a pair of surrogates, + * both on entry and upon return. + * @param limit the limit index of text to be matched. Greater + * than offset for a forward direction match, less than offset for + * a backward direction match. The last character to be + * considered for matching will be text.charAt(limit-1) in the + * forward direction or text.charAt(limit+1) in the backward + * direction. + * @param incremental if true, then assume further characters may + * be inserted at limit and check for partial matching. Otherwise + * assume the text as given is complete. + * @return a match degree value indicating a full match, a partial + * match, or a mismatch. If incremental is false then + * U_PARTIAL_MATCH should never be returned. + */ + virtual UMatchDegree matches(const Replaceable& text, + int32_t& offset, + int32_t limit, + UBool incremental) override; + + /** + * Implement UnicodeMatcher + * @param result Output param to receive the pattern. + * @param escapeUnprintable if True then escape the unprintable characters. + * @return A reference to 'result'. + */ + virtual UnicodeString& toPattern(UnicodeString& result, + UBool escapeUnprintable = false) const override; + + /** + * Implement UnicodeMatcher + * Returns true if this matcher will match a character c, where c + * & 0xFF == v, at offset, in the forward direction (with limit > + * offset). This is used by <tt>RuleBasedTransliterator</tt> for + * indexing. + * @param v the given value + * @return true if this matcher will match a character c, + * where c & 0xFF == v + */ + virtual UBool matchesIndexValue(uint8_t v) const override; + + /** + * Implement UnicodeMatcher + */ + virtual void addMatchSetTo(UnicodeSet& toUnionTo) const override; + + /** + * Implement UnicodeFunctor + */ + virtual void setData(const TransliterationRuleData*) override; + + /** + * Replace characters in 'text' from 'start' to 'limit' with the + * output text of this object. Update the 'cursor' parameter to + * give the cursor position and return the length of the + * replacement text. + * + * @param text the text to be matched + * @param start inclusive start index of text to be replaced + * @param limit exclusive end index of text to be replaced; + * must be greater than or equal to start + * @param cursor output parameter for the cursor position. + * Not all replacer objects will update this, but in a complete + * tree of replacer objects, representing the entire output side + * of a transliteration rule, at least one must update it. + * @return the number of 16-bit code units in the text replacing + * the characters at offsets start..(limit-1) in text + */ + virtual int32_t replace(Replaceable& text, + int32_t start, + int32_t limit, + int32_t& cursor) override; + + /** + * Returns a string representation of this replacer. If the + * result of calling this function is passed to the appropriate + * parser, typically TransliteratorParser, it will produce another + * replacer that is equal to this one. + * @param result the string to receive the pattern. Previous + * contents will be deleted. + * @param escapeUnprintable if true then convert unprintable + * character to their hex escape representations, \\uxxxx or + * \\Uxxxxxxxx. Unprintable characters are defined by + * Utility.isUnprintable(). + * @return a reference to 'result'. + */ + virtual UnicodeString& toReplacerPattern(UnicodeString& result, + UBool escapeUnprintable) const override; + + /** + * Remove any match data. This must be called before performing a + * set of matches with this segment. + */ + void resetMatch(); + + /** + * ICU "poor man's RTTI", returns a UClassID for the actual class. + */ + virtual UClassID getDynamicClassID() const override; + + /** + * ICU "poor man's RTTI", returns a UClassID for this class. + */ + static UClassID U_EXPORT2 getStaticClassID(); + + /** + * Union the set of all characters that may output by this object + * into the given set. + * @param toUnionTo the set into which to union the output characters + */ + virtual void addReplacementSetTo(UnicodeSet& toUnionTo) const override; + + private: + + /** + * The text to be matched. + */ + UnicodeString pattern; + + /** + * Context object that maps stand-ins to matcher and replacer + * objects. + */ + const TransliterationRuleData* data; + + /** + * The segment number, 1-based, or 0 if not a segment. + */ + int32_t segmentNumber; + + /** + * Start offset, in the match text, of the <em>rightmost</em> + * match. + */ + int32_t matchStart; + + /** + * Limit offset, in the match text, of the <em>rightmost</em> + * match. + */ + int32_t matchLimit; + +}; + +U_NAMESPACE_END + +#endif /* #if !UCONFIG_NO_TRANSLITERATION */ + +#endif |