#include <chariter.h>
Public Types | |
| enum | EOrigin { kStart, kCurrent, kEnd, kStart, kCurrent, kEnd } |
| enum | EOrigin { kStart, kCurrent, kEnd, kStart, kCurrent, kEnd } |
 Public Types inherited from ForwardCharacterIterator | |
| enum | { DONE = 0xffff } |
| enum | { DONE = 0xffff } |
Protected Attributes | |
| int32_t | textLength |
| int32_t | pos |
| int32_t | begin |
| int32_t | end |
Detailed Description
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.
The API provides backward compatibility to the Java and older ICU CharacterIterator classes but extends them significantly:
- CharacterIterator is now a subclass of ForwardCharacterIterator.
- 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.
- 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.
- There are new functions for setting and moving the current position without returning a character, for efficiency.
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.
Examples for some of the new functions:
Forward iteration with hasNext():
Forward iteration more similar to loops with the old forward iteration, showing a way to convert simple for() loops:
Backward iteration with setToEnd() and hasPrevious():
Backward iteration with a more traditional for() loop:
Example for random access:
Examples, especially for the old API:
Function processing characters, in this example simple output
Traverse the text from start to finish
Traverse the text backwards, from end to start
Traverse both forward and backward from a given position in the text. Calls to notBoundary() in this example represents some additional stopping criteria.
{for (c = iter.setIndex(pos);c != CharacterIterator.DONE && (Unicode::isLetter(c) || Unicode::isDigit(c));c = iter.next()) {}for (c = iter.setIndex(pos);c != CharacterIterator.DONE && (Unicode::isLetter(c) || Unicode::isDigit(c));c = iter.previous()) {}processChar(c);}}
Creating a StringCharacterIterator and calling the test functions
void CharacterIterator_Example( void ){cout << endl << "===== CharacterIterator_Example: =====" << endl;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;}
ICU 2.0
Member Enumeration Documentation
◆ EOrigin [1/2]
◆ EOrigin [2/2]
Constructor & Destructor Documentation
◆ ~CharacterIterator() [1/2]
|
virtual |
Destructor. ICU 2.0
◆ CharacterIterator() [1/10]
|
protected |
Empty constructor. ICU 2.0
◆ CharacterIterator() [2/10]
|
protected |
Constructor, just setting the length field in this base class. ICU 2.0
◆ CharacterIterator() [3/10]
Constructor, just setting the length and position fields in this base class. ICU 2.0
◆ CharacterIterator() [4/10]
|
protected |
Constructor, just setting the length, start, end, and position fields in this base class. ICU 2.0
◆ CharacterIterator() [5/10]
|
protected |
Copy constructor.
- Parameters
-
that The CharacterIterator to be copied ICU 2.0
◆ ~CharacterIterator() [2/2]
|
virtual |
Destructor. ICU 2.0
◆ CharacterIterator() [6/10]
|
protected |
Empty constructor. ICU 2.0
◆ CharacterIterator() [7/10]
|
protected |
Constructor, just setting the length field in this base class. ICU 2.0
◆ CharacterIterator() [8/10]
Constructor, just setting the length and position fields in this base class. ICU 2.0
◆ CharacterIterator() [9/10]
|
protected |
Constructor, just setting the length, start, end, and position fields in this base class. ICU 2.0
◆ CharacterIterator() [10/10]
|
protected |
Copy constructor.
- Parameters
-
that The CharacterIterator to be copied ICU 2.0
Member Function Documentation
◆ clone() [1/2]
|
pure virtual |
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.
- Returns
- a pointer to a new CharacterIterator ICU 2.0
◆ clone() [2/2]
|
pure virtual |
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.
- Returns
- a pointer to a new CharacterIterator ICU 2.0
◆ current() [1/2]
Returns the code unit the iterator currently refers to.
- Returns
- the current code unit. ICU 2.0
◆ current() [2/2]
Returns the code unit the iterator currently refers to.
- Returns
- the current code unit. ICU 2.0
◆ current32() [1/2]
Returns the code point the iterator currently refers to.
- Returns
- the current code point. ICU 2.0
◆ current32() [2/2]
Returns the code point the iterator currently refers to.
- Returns
- the current code point. ICU 2.0
◆ endIndex() [1/2]
◆ endIndex() [2/2]
◆ first() [1/2]
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().
- Returns
- the first code unit in its iteration range. ICU 2.0
◆ first() [2/2]
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().
- Returns
- the first code unit in its iteration range. ICU 2.0
◆ first32() [1/2]
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.
- Returns
- the first code point in its iteration range. ICU 2.0
◆ first32() [2/2]
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.
- Returns
- the first code point in its iteration range. ICU 2.0
◆ first32PostInc() [1/2]
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().
- Returns
- the first code point in its iteration range. ICU 2.0
◆ first32PostInc() [2/2]
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().
- Returns
- the first code point in its iteration range. ICU 2.0
◆ firstPostInc() [1/2]
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().
- Returns
- the first code unit in its iteration range. ICU 2.0
◆ firstPostInc() [2/2]
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().
- Returns
- the first code unit in its iteration range. ICU 2.0
◆ getIndex() [1/2]
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()).
- Returns
- the numberic index in the text-storage object of the character the iterator currently refers to ICU 2.0
◆ getIndex() [2/2]
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()).
- Returns
- the numberic index in the text-storage object of the character the iterator currently refers to ICU 2.0
◆ getLength() [1/2]
Returns the length of the entire text in the underlying text-storage object.
- Returns
- the length of the entire text in the text-storage object ICU 2.0
◆ getLength() [2/2]
|
inline |
Returns the length of the entire text in the underlying text-storage object.
- Returns
- the length of the entire text in the text-storage object ICU 2.0
◆ getText() [1/2]
|
pure virtual |
Copies the text under iteration into the UnicodeString referred to by "result".
- Parameters
-
result Receives a copy of the text under iteration. ICU 2.0
◆ getText() [2/2]
|
pure virtual |
Copies the text under iteration into the UnicodeString referred to by "result".
- Parameters
-
result Receives a copy of the text under iteration. ICU 2.0
◆ hasPrevious() [1/2]
|
pure virtual |
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.
- Returns
- FALSE if there are no more code units or code points before the current position in the iteration range, return TRUE otherwise. ICU 2.0
◆ hasPrevious() [2/2]
|
pure virtual |
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.
- Returns
- FALSE if there are no more code units or code points before the current position in the iteration range, return TRUE otherwise. ICU 2.0
◆ last() [1/2]
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().
- Returns
- the last code unit. ICU 2.0
◆ last() [2/2]
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().
- Returns
- the last code unit. ICU 2.0
◆ last32() [1/2]
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().
- Returns
- the last code point. ICU 2.0
◆ last32() [2/2]
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().
- Returns
- the last code point. ICU 2.0
◆ move() [1/2]
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.
- Parameters
-
delta the position relative to origin. A positive delta means forward; a negative delta means backward. origin Origin enumeration {kStart, kCurrent, kEnd}
- Returns
- the new position ICU 2.0
◆ move() [2/2]
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.
- Parameters
-
delta the position relative to origin. A positive delta means forward; a negative delta means backward. origin Origin enumeration {kStart, kCurrent, kEnd}
- Returns
- the new position ICU 2.0
◆ move32() [1/2]
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.
- Parameters
-
delta the position relative to origin. A positive delta means forward; a negative delta means backward. origin Origin enumeration {kStart, kCurrent, kEnd}
- Returns
- the new position ICU 2.0
◆ move32() [2/2]
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.
- Parameters
-
delta the position relative to origin. A positive delta means forward; a negative delta means backward. origin Origin enumeration {kStart, kCurrent, kEnd}
- Returns
- the new position ICU 2.0
◆ next() [1/2]
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.
- Returns
- the next code unit. ICU 2.0
◆ next() [2/2]
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.
- Returns
- the next code unit. ICU 2.0
◆ next32() [1/2]
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().
- Returns
- the next code point. ICU 2.0
◆ next32() [2/2]
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().
- Returns
- the next code point. ICU 2.0
◆ operator=() [1/2]
|
protected |
Assignment operator. Sets this CharacterIterator to have the same behavior, as the one passed in.
- Parameters
-
that The CharacterIterator passed in.
- Returns
- the newly set CharacterIterator. ICU 2.0
◆ operator=() [2/2]
|
protected |
Assignment operator. Sets this CharacterIterator to have the same behavior, as the one passed in.
- Parameters
-
that The CharacterIterator passed in.
- Returns
- the newly set CharacterIterator. ICU 2.0
◆ previous() [1/2]
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.
- Returns
- the previous code unit. ICU 2.0
◆ previous() [2/2]
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.
- Returns
- the previous code unit. ICU 2.0
◆ previous32() [1/2]
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.
- Returns
- the previous code point. ICU 2.0
◆ previous32() [2/2]
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.
- Returns
- the previous code point. ICU 2.0
◆ setIndex() [1/2]
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.
- Parameters
-
position the "position"-th code unit in the text-storage object
- Returns
- the "position"-th code unit. ICU 2.0
◆ setIndex() [2/2]
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.
- Parameters
-
position the "position"-th code unit in the text-storage object
- Returns
- the "position"-th code unit. ICU 2.0
◆ setIndex32() [1/2]
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).
- Parameters
-
position the "position"-th code unit in the text-storage object
- Returns
- the "position"-th code point. ICU 2.0
◆ setIndex32() [2/2]
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).
- Parameters
-
position the "position"-th code unit in the text-storage object
- Returns
- the "position"-th code point. ICU 2.0
◆ setToEnd() [1/2]
|
inline |
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().
- Returns
- the end position of the iteration range ICU 2.0
◆ setToEnd() [2/2]
|
inline |
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().
- Returns
- the end position of the iteration range ICU 2.0
◆ setToStart() [1/2]
|
inline |
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().
- Returns
- the start position of the iteration range ICU 2.0
◆ setToStart() [2/2]
|
inline |
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().
- Returns
- the start position of the iteration range ICU 2.0
◆ startIndex() [1/2]
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(). ICU 2.0
◆ startIndex() [2/2]
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(). ICU 2.0
Member Data Documentation
◆ begin
|
protected |
Base class field for the start of the iteration range. ICU 2.0
◆ end
|
protected |
Base class field for the end of the iteration range. ICU 2.0
◆ pos
◆ textLength
|
protected |
Base class text length field. Necessary this for correct getText() and hashCode(). ICU 2.0
The documentation for this class was generated from the following file:
- DerivedData/WebKit/Build/Products/Debug/WebCore.framework/Versions/A/PrivateHeaders/icu/unicode/chariter.h
