Move ICU headers part 1

public/common/unicode/chariter.h

-/*
-********************************************************************
-*
-*   Copyright (C) 1997-2005, International Business Machines
-*   Corporation and others.  All Rights Reserved.
-*
-********************************************************************
-*/
-
-#ifndef CHARITER_H
-#define CHARITER_H
-
-#include "unicode/utypes.h"
-#include "unicode/uobject.h"
-#include "unicode/unistr.h"
-/**
- * \file
- * \brief C++ API: Character Iterator
- */
- 
-U_NAMESPACE_BEGIN
-/**
- * Abstract class that defines an API for forward-only iteration
- * on text objects.
- * This is a minimal interface for iteration without random access
- * or backwards iteration. It is especially useful for wrapping
- * streams with converters into an object for collation or
- * normalization.
- *
- * <p>Characters can be accessed in two ways: as code units or as
- * code points.
- * Unicode code points are 21-bit integers and are the scalar values
- * of Unicode characters. ICU uses the type UChar32 for them.
- * Unicode code units are the storage units of a given
- * Unicode/UCS Transformation Format (a character encoding scheme).
- * With UTF-16, all code points can be represented with either one
- * or two code units ("surrogates").
- * String storage is typically based on code units, while properties
- * of characters are typically determined using code point values.
- * Some processes may be designed to work with sequences of code units,
- * or it may be known that all characters that are important to an
- * algorithm can be represented with single code units.
- * Other processes will need to use the code point access functions.</p>
- *
- * <p>ForwardCharacterIterator provides nextPostInc() to access
- * a code unit and advance an internal position into the text object,
- * similar to a <code>return text[position++]</code>.<br>
- * It provides next32PostInc() to access a code point and advance an internal
- * position.</p>
- *
- * <p>next32PostInc() assumes that the current position is that of
- * the beginning of a code point, i.e., of its first code unit.
- * After next32PostInc(), this will be true again.
- * In general, access to code units and code points in the same
- * iteration loop should not be mixed. In UTF-16, if the current position
- * is on a second code unit (Low Surrogate), then only that code unit
- * is returned even by next32PostInc().</p>
- *
- * <p>For iteration with either function, there are two ways to
- * check for the end of the iteration. When there are no more
- * characters in the text object:
- * <ul>
- * <li>The hasNext() function returns FALSE.</li>
- * <li>nextPostInc() and next32PostInc() return DONE
- *     when one attempts to read beyond the end of the text object.</li>
- * </ul>
- *
- * Example:
- * \code 
- * void function1(ForwardCharacterIterator &it) {
- *     UChar32 c;
- *     while(it.hasNext()) {
- *         c=it.next32PostInc();
- *         // use c
- *     }
- * }
- *
- * void function1(ForwardCharacterIterator &it) {
- *     UChar c;
- *     while((c=it.nextPostInc())!=ForwardCharacterIterator::DONE) {
- *         // use c
- *      }
- *  }
- * \endcode
- * </p>
- *
- * @stable ICU 2.0
- */
-class U_COMMON_API ForwardCharacterIterator : public UObject {
-public:
-    /**
-     * Value returned by most of ForwardCharacterIterator's functions
-     * when the iterator has reached the limits of its iteration.
-     * @stable ICU 2.0
-     */
-    enum { DONE = 0xffff };
-    
-    /**
-     * Destructor.  
-     * @stable ICU 2.0
-     */
-    virtual ~ForwardCharacterIterator();
-    
-    /**
-     * Returns true when both iterators refer to the same
-     * character in the same character-storage object.  
-     * @param that The ForwardCharacterIterator to be compared for equality
-     * @return true when both iterators refer to the same
-     * character in the same character-storage object
-     * @stable ICU 2.0
-     */
-    virtual UBool operator==(const ForwardCharacterIterator& that) const = 0;
-    
-    /**
-     * Returns true when the iterators refer to different
-     * text-storage objects, or to different characters in the
-     * same text-storage object.  
-     * @param that The ForwardCharacterIterator to be compared for inequality
-     * @return true when the iterators refer to different
-     * text-storage objects, or to different characters in the
-     * same text-storage object
-     * @stable ICU 2.0
-     */
-    inline UBool operator!=(const ForwardCharacterIterator& that) const;
-    
-    /**
-     * Generates a hash code for this iterator.  
-     * @return the hash code.
-     * @stable ICU 2.0
-     */
-    virtual int32_t hashCode(void) const = 0;
-    
-    /**
-     * Returns a UClassID for this ForwardCharacterIterator ("poor man's
-     * RTTI").<P> Despite the fact that this function is public,
-     * DO NOT CONSIDER IT PART OF CHARACTERITERATOR'S API! 
-     * @return a UClassID for this ForwardCharacterIterator 
-     * @stable ICU 2.0
-     */
-    virtual UClassID getDynamicClassID(void) const = 0;
-    
-    /**
-     * Gets the current code unit for returning and advances to the next code unit
-     * in the iteration range
-     * (toward endIndex()).  If there are
-     * no more code units to return, returns DONE.
-     * @return the current code unit.
-     * @stable ICU 2.0
-     */
-    virtual UChar         nextPostInc(void) = 0;
-    
-    /**
-     * Gets the current code point for returning and advances to the next code point
-     * in the iteration range
-     * (toward endIndex()).  If there are
-     * no more code points to return, returns DONE.
-     * @return the current code point.
-     * @stable ICU 2.0
-     */
-    virtual UChar32       next32PostInc(void) = 0;
-    
-    /**
-     * Returns FALSE if there are no more code units or code points
-     * at or after the current position in the iteration range.
-     * This is used with nextPostInc() or next32PostInc() in forward
-     * iteration.
-     * @returns FALSE if there are no more code units or code points
-     * at or after the current position in the iteration range.
-     * @stable ICU 2.0
-     */
-    virtual UBool        hasNext() = 0;
-    
-protected:
-    /** Default constructor to be overridden in the implementing class. @stable ICU 2.0*/
-    ForwardCharacterIterator();
-    
-    /** Copy constructor to be overridden in the implementing class. @stable ICU 2.0*/
-    ForwardCharacterIterator(const ForwardCharacterIterator &other);
-    
-    /**
-     * Assignment operator to be overridden in the implementing class.
-     * @stable ICU 2.0
-     */
-    ForwardCharacterIterator &operator=(const ForwardCharacterIterator&) { return *this; }
-};
-
-/**
- * Abstract class that defines an API for iteration
- * on text objects.
- * This is an interface for forward and backward iteration
- * and random access into a text object.
- *
- * <p>The API provides backward compatibility to the Java and older ICU
- * CharacterIterator classes but extends them significantly:
- * <ol>
- * <li>CharacterIterator is now a subclass of ForwardCharacterIterator.</li>
- * <li>While the old API functions provided forward iteration with
- *     "pre-increment" semantics, the new one also provides functions
- *     with "post-increment" semantics. They are more efficient and should
- *     be the preferred iterator functions for new implementations.
- *     The backward iteration always had "pre-decrement" semantics, which
- *     are efficient.</li>
- * <li>Just like ForwardCharacterIterator, it provides access to
- *     both code units and code points. Code point access versions are available
- *     for the old and the new iteration semantics.</li>
- * <li>There are new functions for setting and moving the current position
- *     without returning a character, for efficiency.</li>
- * </ol>
- *
- * See ForwardCharacterIterator for examples for using the new forward iteration
- * functions. For backward iteration, there is also a hasPrevious() function
- * that can be used analogously to hasNext().
- * The old functions work as before and are shown below.</p>
- *
- * <p>Examples for some of the new functions:</p>
- *
- * Forward iteration with hasNext():
- * \code
- * void forward1(CharacterIterator &it) {
- *     UChar32 c;
- *     for(it.setToStart(); it.hasNext();) {
- *         c=it.next32PostInc();
- *         // use c
- *     }
- *  }
- * \endcode
- * Forward iteration more similar to loops with the old forward iteration,
- * showing a way to convert simple for() loops:
- * \code
- * void forward2(CharacterIterator &it) {
- *     UChar c;
- *     for(c=it.firstPostInc(); c!=CharacterIterator::DONE; c=it.nextPostInc()) {
- *          // use c
- *      }
- * }
- * \endcode
- * Backward iteration with setToEnd() and hasPrevious():
- * \code
- *  void backward1(CharacterIterator &it) {
- *      UChar32 c;
- *      for(it.setToEnd(); it.hasPrevious();) {
- *         c=it.previous32();
- *          // use c
- *      }
- *  }
- * \endcode
- * Backward iteration with a more traditional for() loop:
- * \code
- * void backward2(CharacterIterator &it) {
- *     UChar c;
- *     for(c=it.last(); c!=CharacterIterator::DONE; c=it.previous()) {
- *         // use c
- *      }
- *  }
- * \endcode
- *
- * Example for random access:
- * \code
- *  void random(CharacterIterator &it) {
- *      // set to the third code point from the beginning
- *      it.move32(3, CharacterIterator::kStart);
- *      // get a code point from here without moving the position
- *      UChar32 c=it.current32();
- *      // get the position
- *      int32_t pos=it.getIndex();
- *      // get the previous code unit
- *      UChar u=it.previous();
- *      // move back one more code unit
- *      it.move(-1, CharacterIterator::kCurrent);
- *      // set the position back to where it was
- *      // and read the same code point c and move beyond it
- *      it.setIndex(pos);
- *      if(c!=it.next32PostInc()) {
- *          exit(1); // CharacterIterator inconsistent
- *      }
- *  }
- * \endcode
- *
- * <p>Examples, especially for the old API:</p>
- *
- * Function processing characters, in this example simple output
- * <pre>
- * \code
- *  void processChar( UChar c )
- *  {
- *      cout << " " << c;
- *  }
- * \endcode
- * </pre>
- * Traverse the text from start to finish
- * <pre> 
- * \code
- *  void traverseForward(CharacterIterator& iter)
- *  {
- *      for(UChar c = iter.first(); c != CharacterIterator.DONE; c = iter.next()) {
- *          processChar(c);
- *      }
- *  }
- * \endcode
- * </pre>
- * Traverse the text backwards, from end to start
- * <pre>
- * \code
- *  void traverseBackward(CharacterIterator& iter)
- *  {
- *      for(UChar c = iter.last(); c != CharacterIterator.DONE; c = iter.previous()) {
- *          processChar(c);
- *      }
- *  }
- * \endcode
- * </pre>
- * Traverse both forward and backward from a given position in the text. 
- * Calls to notBoundary() in this example represents some additional stopping criteria.
- * <pre>
- * \code
- * void traverseOut(CharacterIterator& iter, int32_t pos)
- * {
- *      UChar c;
- *      for (c = iter.setIndex(pos);
- *      c != CharacterIterator.DONE && (Unicode::isLetter(c) || Unicode::isDigit(c));
- *          c = iter.next()) {}
- *      int32_t end = iter.getIndex();
- *      for (c = iter.setIndex(pos);
- *          c != CharacterIterator.DONE && (Unicode::isLetter(c) || Unicode::isDigit(c));
- *          c = iter.previous()) {}
- *      int32_t start = iter.getIndex() + 1;
- *  
- *      cout << "start: " << start << " end: " << end << endl;
- *      for (c = iter.setIndex(start); iter.getIndex() < end; c = iter.next() ) {
- *          processChar(c);
- *     }
- *  }
- * \endcode
- * </pre>
- * Creating a StringCharacterIterator and calling the test functions
- * <pre>
- * \code
- *  void CharacterIterator_Example( void )
- *   {
- *       cout << endl << "===== CharacterIterator_Example: =====" << endl;
- *       UnicodeString text("Ein kleiner Satz.");
- *       StringCharacterIterator iterator(text);
- *       cout << "----- traverseForward: -----------" << endl;
- *       traverseForward( iterator );
- *       cout << endl << endl << "----- traverseBackward: ----------" << endl;
- *       traverseBackward( iterator );
- *       cout << endl << endl << "----- traverseOut: ---------------" << endl;
- *       traverseOut( iterator, 7 );
- *       cout << endl << endl << "-----" << endl;
- *   }
- * \endcode
- * </pre>
- *
- * @stable ICU 2.0
- */
-class U_COMMON_API CharacterIterator : public ForwardCharacterIterator {
-public:
-    /**
-     * Origin enumeration for the move() and move32() functions.
-     * @stable ICU 2.0
-     */
-    enum EOrigin { kStart, kCurrent, kEnd };
-
-    /**
-     * Returns a pointer to a new CharacterIterator of the same
-     * concrete class as this one, and referring to the same
-     * character in the same text-storage object as this one.  The
-     * caller is responsible for deleting the new clone.  
-     * @return a pointer to a new CharacterIterator
-     * @stable ICU 2.0
-     */
-    virtual CharacterIterator* clone(void) const = 0;
-
-    /**
-     * Sets the iterator to refer to the first code unit in its
-     * iteration range, and returns that code unit.
-     * This can be used to begin an iteration with next().
-     * @return the first code unit in its iteration range.
-     * @stable ICU 2.0
-     */
-    virtual UChar         first(void) = 0;
-
-    /**
-     * Sets the iterator to refer to the first code unit in its
-     * iteration range, returns that code unit, and moves the position
-     * to the second code unit. This is an alternative to setToStart()
-     * for forward iteration with nextPostInc().
-     * @return the first code unit in its iteration range.
-     * @stable ICU 2.0
-     */
-    virtual UChar         firstPostInc(void);
-
-    /**
-     * Sets the iterator to refer to the first code point in its
-     * iteration range, and returns that code unit,
-     * This can be used to begin an iteration with next32().
-     * Note that an iteration with next32PostInc(), beginning with,
-     * e.g., setToStart() or firstPostInc(), is more efficient.
-     * @return the first code point in its iteration range.
-     * @stable ICU 2.0
-     */
-    virtual UChar32       first32(void) = 0;
-
-    /**
-     * Sets the iterator to refer to the first code point in its
-     * iteration range, returns that code point, and moves the position
-     * to the second code point. This is an alternative to setToStart()
-     * for forward iteration with next32PostInc().
-     * @return the first code point in its iteration range.
-     * @stable ICU 2.0
-     */
-    virtual UChar32       first32PostInc(void);
-
-    /**
-     * Sets the iterator to refer to the first code unit or code point in its
-     * iteration range. This can be used to begin a forward
-     * iteration with nextPostInc() or next32PostInc().
-     * @return the start position of the iteration range
-     * @stable ICU 2.0
-     */
-    inline int32_t    setToStart();
-
-    /**
-     * Sets the iterator to refer to the last code unit in its
-     * iteration range, and returns that code unit.
-     * This can be used to begin an iteration with previous().
-     * @return the last code unit.
-     * @stable ICU 2.0
-     */
-    virtual UChar         last(void) = 0;
-        
-    /**
-     * Sets the iterator to refer to the last code point in its
-     * iteration range, and returns that code unit.
-     * This can be used to begin an iteration with previous32().
-     * @return the last code point.
-     * @stable ICU 2.0
-     */
-    virtual UChar32       last32(void) = 0;
-
-    /**
-     * Sets the iterator to the end of its iteration range, just behind
-     * the last code unit or code point. This can be used to begin a backward
-     * iteration with previous() or previous32().
-     * @return the end position of the iteration range
-     * @stable ICU 2.0
-     */
-    inline int32_t    setToEnd();
-
-    /**
-     * Sets the iterator to refer to the "position"-th code unit
-     * in the text-storage object the iterator refers to, and
-     * returns that code unit.  
-     * @param position the "position"-th code unit in the text-storage object
-     * @return the "position"-th code unit.
-     * @stable ICU 2.0
-     */
-    virtual UChar         setIndex(int32_t position) = 0;
-
-    /**
-     * Sets the iterator to refer to the beginning of the code point
-     * that contains the "position"-th code unit
-     * in the text-storage object the iterator refers to, and
-     * returns that code point.
-     * The current position is adjusted to the beginning of the code point
-     * (its first code unit).
-     * @param position the "position"-th code unit in the text-storage object
-     * @return the "position"-th code point.
-     * @stable ICU 2.0
-     */
-    virtual UChar32       setIndex32(int32_t position) = 0;
-
-    /**
-     * Returns the code unit the iterator currently refers to. 
-     * @return the current code unit. 
-     * @stable ICU 2.0
-     */
-    virtual UChar         current(void) const = 0;
-        
-    /**
-     * Returns the code point the iterator currently refers to.  
-     * @return the current code point.
-     * @stable ICU 2.0
-     */
-    virtual UChar32       current32(void) const = 0;
-        
-    /**
-     * Advances to the next code unit in the iteration range
-     * (toward endIndex()), and returns that code unit.  If there are
-     * no more code units to return, returns DONE.
-     * @return the next code unit.
-     * @stable ICU 2.0
-     */
-    virtual UChar         next(void) = 0;
-        
-    /**
-     * Advances to the next code point in the iteration range
-     * (toward endIndex()), and returns that code point.  If there are
-     * no more code points to return, returns DONE.
-     * Note that iteration with "pre-increment" semantics is less
-     * efficient than iteration with "post-increment" semantics
-     * that is provided by next32PostInc().
-     * @return the next code point.
-     * @stable ICU 2.0
-     */
-    virtual UChar32       next32(void) = 0;
-        
-    /**
-     * Advances to the previous code unit in the iteration range
-     * (toward startIndex()), and returns that code unit.  If there are
-     * no more code units to return, returns DONE.  
-     * @return the previous code unit.
-     * @stable ICU 2.0
-     */
-    virtual UChar         previous(void) = 0;
-
-    /**
-     * Advances to the previous code point in the iteration range
-     * (toward startIndex()), and returns that code point.  If there are
-     * no more code points to return, returns DONE. 
-     * @return the previous code point. 
-     * @stable ICU 2.0
-     */
-    virtual UChar32       previous32(void) = 0;
-
-    /**
-     * Returns FALSE if there are no more code units or code points
-     * before the current position in the iteration range.
-     * This is used with previous() or previous32() in backward
-     * iteration.
-     * @return FALSE if there are no more code units or code points
-     * before the current position in the iteration range, return TRUE otherwise.
-     * @stable ICU 2.0
-     */
-    virtual UBool        hasPrevious() = 0;
-
-    /**
-     * Returns the numeric index in the underlying text-storage
-     * object of the character returned by first().  Since it's
-     * possible to create an iterator that iterates across only
-     * part of a text-storage object, this number isn't
-     * necessarily 0.  
-     * @returns the numeric index in the underlying text-storage
-     * object of the character returned by first().
-     * @stable ICU 2.0
-     */
-    inline int32_t       startIndex(void) const;
-        
-    /**
-     * Returns the numeric index in the underlying text-storage
-     * object of the position immediately BEYOND the character
-     * returned by last().  
-     * @return the numeric index in the underlying text-storage
-     * object of the position immediately BEYOND the character
-     * returned by last().
-     * @stable ICU 2.0
-     */
-    inline int32_t       endIndex(void) const;
-        
-    /**
-     * Returns the numeric index in the underlying text-storage
-     * object of the character the iterator currently refers to
-     * (i.e., the character returned by current()).  
-     * @return the numberic index in the text-storage object of 
-     * the character the iterator currently refers to
-     * @stable ICU 2.0
-     */
-    inline int32_t       getIndex(void) const;
-
-    /**
-     * Returns the length of the entire text in the underlying
-     * text-storage object.
-     * @return the length of the entire text in the text-storage object
-     * @stable ICU 2.0
-     */
-    inline int32_t           getLength() const;
-
-    /**
-     * Moves the current position relative to the start or end of the
-     * iteration range, or relative to the current position itself.
-     * The movement is expressed in numbers of code units forward
-     * or backward by specifying a positive or negative delta.
-     * @param delta the position relative to origin. A positive delta means forward;
-     * a negative delta means backward.
-     * @param origin Origin enumeration {kStart, kCurrent, kEnd}
-     * @return the new position
-     * @stable ICU 2.0
-     */
-    virtual int32_t      move(int32_t delta, EOrigin origin) = 0;
-
-    /**
-     * Moves the current position relative to the start or end of the
-     * iteration range, or relative to the current position itself.
-     * The movement is expressed in numbers of code points forward
-     * or backward by specifying a positive or negative delta.
-     * @param delta the position relative to origin. A positive delta means forward;
-     * a negative delta means backward.
-     * @param origin Origin enumeration {kStart, kCurrent, kEnd}
-     * @return the new position
-     * @stable ICU 2.0
-     */
-    virtual int32_t      move32(int32_t delta, EOrigin origin) = 0;
-
-    /**
-     * Copies the text under iteration into the UnicodeString
-     * referred to by "result".  
-     * @param result Receives a copy of the text under iteration.  
-     * @stable ICU 2.0
-     */
-    virtual void            getText(UnicodeString&  result) = 0;
-
-protected:
-    /**
-     * Empty constructor.
-     * @stable ICU 2.0
-     */
-    CharacterIterator();
-
-    /**
-     * Constructor, just setting the length field in this base class.
-     * @stable ICU 2.0
-     */
-    CharacterIterator(int32_t length);
-
-    /**
-     * Constructor, just setting the length and position fields in this base class.
-     * @stable ICU 2.0
-     */
-    CharacterIterator(int32_t length, int32_t position);
-
-    /**
-     * Constructor, just setting the length, start, end, and position fields in this base class.
-     * @stable ICU 2.0
-     */
-    CharacterIterator(int32_t length, int32_t textBegin, int32_t textEnd, int32_t position);
-  
-    /**
-     * Copy constructor.
-     *
-     * @param that The CharacterIterator to be copied
-     * @stable ICU 2.0
-     */
-    CharacterIterator(const CharacterIterator &that);
-
-    /**
-     * Assignment operator.  Sets this CharacterIterator to have the same behavior,
-     * as the one passed in.
-     * @param that The CharacterIterator passed in.
-     * @return the newly set CharacterIterator.
-     * @stable ICU 2.0
-     */
-    CharacterIterator &operator=(const CharacterIterator &that);
-
-    /**
-     * Base class text length field.
-     * Necessary this for correct getText() and hashCode().
-     * @stable ICU 2.0
-     */
-    int32_t textLength;
-
-    /**
-     * Base class field for the current position.
-     * @stable ICU 2.0
-     */
-    int32_t  pos;
-
-    /**
-     * Base class field for the start of the iteration range.
-     * @stable ICU 2.0
-     */
-    int32_t  begin;
-
-    /**
-     * Base class field for the end of the iteration range.
-     * @stable ICU 2.0
-     */
-    int32_t  end;
-};
-
-inline UBool
-ForwardCharacterIterator::operator!=(const ForwardCharacterIterator& that) const {
-    return !operator==(that);
-}
-
-inline int32_t
-CharacterIterator::setToStart() {
-    return move(0, kStart);
-}
-
-inline int32_t
-CharacterIterator::setToEnd() {
-    return move(0, kEnd);
-}
-
-inline int32_t
-CharacterIterator::startIndex(void) const {
-    return begin;
-}
-
-inline int32_t
-CharacterIterator::endIndex(void) const {
-    return end;
-}
-
-inline int32_t
-CharacterIterator::getIndex(void) const {
-    return pos;
-}
-
-inline int32_t
-CharacterIterator::getLength(void) const {
-    return textLength;
-}
-
-U_NAMESPACE_END
-#endif