| // © 2016 and later: Unicode, Inc. and others. |
| // License & terms of use: http://www.unicode.org/copyright.html |
| /* |
| * Copyright (C) 2001-2005, International Business Machines Corporation and others. All Rights Reserved. |
| ********************************************************************** |
| * Date Name Description |
| * 07/18/01 aliu Creation. |
| ********************************************************************** |
| */ |
| #ifndef UNIMATCH_H |
| #define UNIMATCH_H |
| |
| #include "unicode/utypes.h" |
| |
| /** |
| * \file |
| * \brief C++ API: Unicode Matcher |
| */ |
| |
| |
| U_NAMESPACE_BEGIN |
| |
| class Replaceable; |
| class UnicodeString; |
| class UnicodeSet; |
| |
| /** |
| * Constants returned by <code>UnicodeMatcher::matches()</code> |
| * indicating the degree of match. |
| * @stable ICU 2.4 |
| */ |
| enum UMatchDegree { |
| /** |
| * Constant returned by <code>matches()</code> indicating a |
| * mismatch between the text and this matcher. The text contains |
| * a character which does not match, or the text does not contain |
| * all desired characters for a non-incremental match. |
| * @stable ICU 2.4 |
| */ |
| U_MISMATCH, |
| |
| /** |
| * Constant returned by <code>matches()</code> indicating a |
| * partial match between the text and this matcher. This value is |
| * only returned for incremental match operations. All characters |
| * of the text match, but more characters are required for a |
| * complete match. Alternatively, for variable-length matchers, |
| * all characters of the text match, and if more characters were |
| * supplied at limit, they might also match. |
| * @stable ICU 2.4 |
| */ |
| U_PARTIAL_MATCH, |
| |
| /** |
| * Constant returned by <code>matches()</code> indicating a |
| * complete match between the text and this matcher. For an |
| * incremental variable-length match, this value is returned if |
| * the given text matches, and it is known that additional |
| * characters would not alter the extent of the match. |
| * @stable ICU 2.4 |
| */ |
| U_MATCH |
| }; |
| |
| /** |
| * <code>UnicodeMatcher</code> defines a protocol for objects that can |
| * match a range of characters in a Replaceable string. |
| * @stable ICU 2.4 |
| */ |
| class U_COMMON_API UnicodeMatcher /* not : public UObject because this is an interface/mixin class */ { |
| |
| public: |
| /** |
| * Destructor. |
| * @stable ICU 2.4 |
| */ |
| virtual ~UnicodeMatcher(); |
| |
| /** |
| * Return a UMatchDegree value indicating the degree of match for |
| * the given text at the given offset. Zero, one, or more |
| * characters may be matched. |
| * |
| * Matching in the forward direction is indicated by limit > |
| * offset. Characters from offset forwards to limit-1 will be |
| * considered for matching. |
| * |
| * Matching in the reverse direction is indicated by limit < |
| * offset. Characters from offset backwards to limit+1 will be |
| * considered for matching. |
| * |
| * If limit == offset then the only match possible is a zero |
| * character match (which subclasses may implement if desired). |
| * |
| * As a side effect, advance the offset parameter to the limit of |
| * the matched substring. In the forward direction, this will be |
| * the index of the last matched character plus one. In the |
| * reverse direction, this will be the index of the last matched |
| * character minus one. |
| * |
| * <p>Note: This method is not const because some classes may |
| * modify their state as the result of a match. |
| * |
| * @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. |
| * @stable ICU 2.4 |
| */ |
| virtual UMatchDegree matches(const Replaceable& text, |
| int32_t& offset, |
| int32_t limit, |
| UBool incremental) = 0; |
| |
| /** |
| * Returns a string representation of this matcher. If the result of |
| * calling this function is passed to the appropriate parser, it |
| * will produce another matcher 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 those other than |
| * U+000A, U+0020..U+007E. |
| * @stable ICU 2.4 |
| */ |
| virtual UnicodeString& toPattern(UnicodeString& result, |
| UBool escapeUnprintable = FALSE) const = 0; |
| |
| /** |
| * 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. |
| * @stable ICU 2.4 |
| */ |
| virtual UBool matchesIndexValue(uint8_t v) const = 0; |
| |
| /** |
| * Union the set of all characters that may be matched by this object |
| * into the given set. |
| * @param toUnionTo the set into which to union the source characters |
| * @stable ICU 2.4 |
| */ |
| virtual void addMatchSetTo(UnicodeSet& toUnionTo) const = 0; |
| }; |
| |
| U_NAMESPACE_END |
| |
| #endif |
