ANTLR Support Libraries 2.7.1+
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#include <InputBuffer.hpp>
Public Member Functions | |
InputBuffer () | |
virtual | ~InputBuffer () |
virtual void | reset (void) |
Reset the input buffer to empty state. | |
void | commit (void) |
virtual void | consume () |
virtual void | fill (unsigned int amount) |
virtual int | getChar ()=0 |
virtual int | LA (unsigned int i) |
virtual unsigned int | mark () |
virtual bool | isMarked () const |
Are there any marks active in the InputBuffer. | |
virtual void | rewind (unsigned int mark) |
virtual unsigned int | entries () const |
std::string | getLAChars () const |
std::string | getMarkedChars () const |
Protected Member Functions | |
void | syncConsume () |
Protected Attributes | |
unsigned int | nMarkers |
unsigned int | markerOffset |
unsigned int | numToConsume |
CircularQueue< int > | queue |
Private Member Functions | |
InputBuffer (const InputBuffer &other) | |
InputBuffer & | operator= (const InputBuffer &other) |
A Stream of characters fed to the lexer from a InputStream that can be rewound via mark()/rewind() methods.
A dynamic array is used to buffer up all the input characters. Normally, "k" characters are stored in the buffer. More characters may be stored during guess mode (testing syntactic predicate), or when LT(i>k) is referenced. Consumption of characters is deferred. In other words, reading the next character is not done by conume(), but deferred until needed by LA or LT.
InputBuffer::InputBuffer | ( | ) | [inline] |
Create a character buffer
virtual InputBuffer::~InputBuffer | ( | ) | [inline, virtual] |
InputBuffer::InputBuffer | ( | const InputBuffer & | other | ) | [private] |
void InputBuffer::commit | ( | void | ) | [inline] |
This method updates the state of the input buffer so that the text matched since the most recent mark() is no longer held by the buffer. So, you either do a mark/rewind for failed predicate or mark/commit to keep on parsing without rewinding the input.
virtual void InputBuffer::consume | ( | ) | [inline, virtual] |
Mark another character for deferred consumption
unsigned int InputBuffer::entries | ( | ) | const [virtual] |
Get the number of non-consumed characters
void InputBuffer::fill | ( | unsigned int | amount | ) | [virtual] |
Ensure that the character buffer is sufficiently full
virtual int InputBuffer::getChar | ( | ) | [pure virtual] |
Override this in subclasses to get the next character
Implemented in CharBuffer, and CharInputBuffer.
std::string InputBuffer::getLAChars | ( | void | ) | const |
get the current lookahead characters as a string
std::string InputBuffer::getMarkedChars | ( | void | ) | const |
get the current marked characters as a string
virtual bool InputBuffer::isMarked | ( | ) | const [inline, virtual] |
Are there any marks active in the InputBuffer.
virtual int InputBuffer::LA | ( | unsigned int | i | ) | [inline, virtual] |
Get a lookahead character
unsigned int InputBuffer::mark | ( | ) | [virtual] |
Return an integer marker that can be used to rewind the buffer to its current state.
InputBuffer& InputBuffer::operator= | ( | const InputBuffer & | other | ) | [private] |
virtual void InputBuffer::reset | ( | void | ) | [inline, virtual] |
Reset the input buffer to empty state.
Reimplemented in CharInputBuffer.
void InputBuffer::rewind | ( | unsigned int | mark | ) | [virtual] |
Rewind the character buffer to a marker.
mark | Marker returned previously from mark() |
void InputBuffer::syncConsume | ( | ) | [inline, protected] |
Sync up deferred consumption
unsigned int InputBuffer::markerOffset [protected] |
unsigned int InputBuffer::nMarkers [protected] |
unsigned int InputBuffer::numToConsume [protected] |
CircularQueue<int> InputBuffer::queue [protected] |