scuffed-code/icu4c/source/i18n/symtable.h
Alan Liu 8557348fa3 ICU-486 Implement anchors.
X-SVN-Rev: 2401
2000-08-30 20:43:25 +00:00

65 lines
2.3 KiB
C++

/*
**********************************************************************
* Copyright (c) 2000, International Business Machines
* Corporation and others. All Rights Reserved.
**********************************************************************
* Date Name Description
* 02/04/00 aliu Creation.
**********************************************************************
*/
#ifndef SYMTABLE_H
#define SYMTABLE_H
class ParsePosition;
class UnicodeSet;
class UnicodeString;
/**
* An interface that maps strings to objects. This interface defines
* both lookup protocol and parsing. This allows different components
* to share a symbol table and to handle name parsing uniformly. It
* is expected that client parse code look for the SYMBOL_REF
* character and, when seen, attempt to parse the characters after it
* using parseReference().
*
* <p>Currently, RuleBasedTransliterator and UnicodeSet use this
* interface to share variable definitions.
*/
class SymbolTable {
public:
/**
* The character preceding a symbol reference name.
*/
enum { SYMBOL_REF = 0x0024 /*$*/ };
/**
* Lookup the characters associated with this string and return it.
* Return <tt>NULL</tt> if no such name exists. The resultant
* string may have length zero.
*/
virtual const UnicodeString* lookup(const UnicodeString& s) const = 0;
/**
* Lookup the UnicodeSet associated with the given character, and
* return it. Return <tt>null</tt> if not found.
*/
virtual const UnicodeSet* lookupSet(UChar ch) const = 0;
/**
* Parse a symbol reference name from the given string, starting
* at the given position. If no valid symbol reference name is
* found, return an empty string.
* @param text the text to parse for the name
* @param pos on entry, the index of the first character to parse.
* This is the character following the SYMBOL_REF character. On
* exit, the index after the last parsed character.
* @param limit the index after the last character to be parsed.
* @return the parsed name or an empty string.
*/
virtual UnicodeString parseReference(const UnicodeString& text,
ParsePosition& pos, int32_t limit) const = 0;
};
#endif