/* ********************************************************************** * Copyright (c) 2001-2002, International Business Machines * Corporation and others. All Rights Reserved. ********************************************************************** */ #ifndef _UPROPSET_H_ #define _UPROPSET_H_ #include "unicode/utypes.h" #include "unicode/uobject.h" #include "unicode/uscript.h" U_NAMESPACE_BEGIN class UnicodeString; class UnicodeSet; class ParsePosition; class Hashtable; /** * INTERNAL CLASS implementing the UnicodeSet properties as outlined * at: * * http://oss.software.ibm.com/cvs/icu/~checkout~/icuhtml/design/unicodeset_properties.html * * Recognized syntax: * * [:foo:] [:^foo:] - white space not allowed within "[:" or ":]" * \p{foo} \P{foo} - white space not allowed within "\p" or "\P" * * Other than the above restrictions, white space is ignored. Case * is ignored except in "\p" and "\P". * * This class cannot be instantiated. It has a public static method, * createPropertySet(), with takes a pattern to be parsed and returns * a new UnicodeSet. Another public static method, * resemblesPattern(), returns true if a given pattern string appears * to be a property set pattern, and therefore should be passed in to * createPropertySet(). * * NOTE: Current implementation is incomplete. The following list * indicates which properties are supported. * * + GeneralCategory * + CombiningClass * + BidiClass * DecompositionType * + NumericValue * NumericType * EastAsianWidth * LineBreak * JoiningType * + Script * + Binary properties * * '+' indicates a supported property. * * @author Alan Liu * @internal */ class UnicodePropertySet /* not : public UObject because all methods are static */ { public: //---------------------------------------------------------------- // Public API //---------------------------------------------------------------- /** * Return true if the given position, in the given pattern, appears * to be the start of a property set pattern [:foo:], \p{foo}, or * \P{foo}. */ static UBool resemblesPattern(const UnicodeString& pattern, int32_t pos); /** * Create a UnicodeSet by parsing the given pattern at the given * parse position. * * @param pattern the pattern string * @param ppos on entry, the position at which to begin parsing. * This shold be one of the locations marked '^': * * [:blah:] \p{blah} \P{blah} * ^ % ^ % ^ % * * On return, the position after the last character parsed, that is, * the locations marked '%'. If the parse fails, ppos is returned * unchanged. * @return a newly-constructed UnicodeSet object, or null upon * failure. */ static UnicodeSet* createFromPattern(const UnicodeString& pattern, ParsePosition& ppos); typedef UnicodeSet* (*SetFactory)(const UnicodeString& valueName); private: //---------------------------------------------------------------- // Property set factory static methods // NOTE: This will change/go away when we implement UCharacter // based property retrieval. //---------------------------------------------------------------- static UnicodeSet* createNumericValueSet(const UnicodeString& valueName); /** * Given a combining class name, or number, create a corresponding * set and return it. The name may be numeric, as in \p{cc=0}, or * symbolic, as in \p{cc=Below Left}. If the name is invalid, * return an empty set. */ static UnicodeSet* createCombiningClassSet(const UnicodeString& valueName); /** * Given a bidi class name create a corresponding set and return * it. If the name is invalid, return NULL. */ static UnicodeSet* createBidiClassSet(const UnicodeString& valueName); /** * Given a general category value name, create a corresponding * set and return it, or return null if the name is invalid. * @param valueName a pre-munged general category value name */ static UnicodeSet* createCategorySet(const UnicodeString& valueName); /** * Given a script value name, create a corresponding set and * return it, or return null if the name is invalid. * @param valueName a pre-munged script value name */ static UnicodeSet* createScriptSet(const UnicodeString& valueName); /** * Given a binary property name, create a corresponding * set and return it, or return null if the name is invalid. * @param valueName a pre-munged binary property name */ static UnicodeSet* createBinaryPropertySet(const UnicodeString& valueName); //---------------------------------------------------------------- // Utility methods //---------------------------------------------------------------- /** * Returns a UnicodeSet for the given category. This set is * cached and returned again if this method is called again with * the same parameter. * * Callers MUST NOT MODIFY the returned set. */ static const UnicodeSet& getCategorySet(int32_t cat); /** * Returns a UnicodeSet for the given script. This set is * cached and returned again if this method is called again with * the same parameter. * * Callers MUST NOT MODIFY the returned set. */ static const UnicodeSet& getScriptSet(UScriptCode script); /** * Given a string, munge it to upper case and lose the whitespace. * So "General Category " becomes "GENERALCATEGORY". We munge all * type and value strings, and store all type and value keys * pre-munged. */ static UnicodeString munge(const UnicodeString& str, int32_t start, int32_t limit); /** * Skip over a sequence of zero or more white space characters * at pos. Return the index of the first non-white-space character * at or after pos, or str.length(), if there is none. */ static int32_t skipWhitespace(const UnicodeString& str, int32_t pos); //---------------------------------------------------------------- // Generic filter-based scanning code // // NOTE: In general, we don't want to do this! This is a temporary // implementation until we have time for something that examines // the underlying UCharacter data structures in an intelligent // way. Iterating over all code points is dumb. What we want to // do, for instance, is iterate over internally-stored ranges // of characters that have a given property. //---------------------------------------------------------------- /** * A filter that returns TRUE if the given code point should be * included in the UnicodeSet being constructed. */ typedef UBool (*Filter)(UChar32 codePoint, void* context); /** * Set the given UnicodeSet to contain all code points for which * filter returns TRUE. The context parameter is passed unchanged * to the filter function. */ static void initSetFromFilter(UnicodeSet& set, Filter filter, void* context); //---------------------------------------------------------------- // Type and value name maps //---------------------------------------------------------------- /** * Add a type mapping to the name map. */ static void addType(const UnicodeString& shortName, const UnicodeString& longName, SetFactory factory); /** * Add a value mapping to the name map. */ static void addValue(Hashtable* map, const UnicodeString& shortName, const UnicodeString& longName, int32_t value); static void init(); private: // do not instantiate UnicodePropertySet(); //---------------------------------------------------------------- // SetFactory <=> void* // I don't know why the compiler won't cast between these types. // They should be interconvertible. Does C++ distinguish between // pointers into code and pointers into data? In any case, we // convert between these types in a safe way here. //---------------------------------------------------------------- union SetFactoryTok { void* voidPointer; SetFactory functionPointer; }; inline static void* setFactoryToVoidPtr(SetFactory f) { SetFactoryTok tok; tok.functionPointer = f; return tok.voidPointer; } inline static SetFactory voidPtrToSetFactory(void* p) { SetFactoryTok tok; tok.voidPointer = p; return tok.functionPointer; } }; U_NAMESPACE_END #endif