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/*
**********************************************************************
* Copyright (c) 2002, International Business Machines Corporation
* and others. All Rights Reserved.
**********************************************************************
* Date Name Description
* 01/14/2002 aliu Creation.
**********************************************************************
*/
#ifndef UNIREPL_H
#define UNIREPL_H
#include "unicode/utypes.h"
U_NAMESPACE_BEGIN
class Replaceable;
class UnicodeString;
class UnicodeSet;
/**
* <code>UnicodeReplacer</code> defines a protocol for objects that
* replace a range of characters in a Replaceable string with output
* text. The replacement is done via the Replaceable API so as to
* preserve out-of-band data.
*
* <p>This is a mixin class.
* @author Alan Liu
* @draft ICU 2.4
*/
class U_I18N_API UnicodeReplacer /* not : public UObject because this is an interface/mixin class */ {
public:
/**
* Destructor.
* @draft ICU 2.4
*/
virtual ~UnicodeReplacer();
/**
* 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
* @draft ICU 2.4
*/
virtual int32_t replace(Replaceable& text,
int32_t start,
int32_t limit,
int32_t& cursor) = 0;
/**
* 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'.
* @draft ICU 2.4
*/
virtual UnicodeString& toReplacerPattern(UnicodeString& result,
UBool escapeUnprintable) const = 0;
/**
* 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
* @draft ICU 2.4
*/
virtual void addReplacementSetTo(UnicodeSet& toUnionTo) const = 0;
};
U_NAMESPACE_END
#endif