Antlr.Runtime.DFA Class Reference

A DFA implemented as a set of transition tables. More...

Collaboration diagram for Antlr.Runtime.DFA:

[legend]

List of all members.

Public Member Functions
delegate int	SpecialStateTransitionHandler (DFA dfa, int s, IIntStream input)
int	Predict (IIntStream input)
	From the input stream, predict what alternative will succeed using this DFA (representing the covering regular approximation to the underlying CFL).
virtual void	Error (NoViableAltException nvae)
	A hook for debugging interface.
virtual int	SpecialStateTransition (int s, IIntStream input)
int	SpecialTransition (int state, int symbol)
Static Public Member Functions
static short[]	UnpackEncodedString (string encodedString)
static short[][]	UnpackEncodedStringArray (string[] encodedStrings)
static char[]	UnpackEncodedStringToUnsignedChars (string encodedString)
Public Attributes
SpecialStateTransitionHandler	specialStateTransitionHandler
const bool	debug = false
Protected Member Functions
void	NoViableAlt (int s, IIntStream input)
Protected Attributes
short[]	eot
short[]	eof
char[]	min
char[]	max
short[]	accept
short[]	special
short[][]	transition
int	decisionNumber
BaseRecognizer	recognizer
	Which recognizer encloses this DFA? Needed to check backtracking.
Properties
virtual string	Description [get]

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Detailed Description

A DFA implemented as a set of transition tables.

Any state that has a semantic predicate edge is special; those states are generated with if-then-else structures in a SpecialStateTransition() which is generated by cyclicDFA template.

There are at most 32767 states (16-bit signed short). Could get away with byte sometimes but would have to generate different types and the simulation code too.

As a point of reference, the Tokens rule DFA for the lexer in the Java grammar sample has approximately 326 states.

Definition at line 57 of file DFA.cs.

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Member Function Documentation

delegate int Antlr.Runtime.DFA.SpecialStateTransitionHandler	(	DFA	dfa,
		int	s,
		IIntStream	input
	)

int Antlr.Runtime.DFA.Predict

(

IIntStream

input

)

From the input stream, predict what alternative will succeed using this DFA (representing the covering regular approximation to the underlying CFL).

Parameters:

input

Input stream

Returns:

Return an alternative number 1..n. Throw an exception upon error.

Definition at line 87 of file DFA.cs.

void Antlr.Runtime.DFA.NoViableAlt	(	int	s,
		IIntStream	input
	)			[protected]

Definition at line 189 of file DFA.cs.

virtual void Antlr.Runtime.DFA.Error

(

NoViableAltException

nvae

)

[virtual]

A hook for debugging interface.

Parameters:

nvae

Definition at line 209 of file DFA.cs.

virtual int Antlr.Runtime.DFA.SpecialStateTransition	(	int	s,
		IIntStream	input
	)			[virtual]

Definition at line 211 of file DFA.cs.

static short [] Antlr.Runtime.DFA.UnpackEncodedString

(

string

encodedString

)

[static]

Definition at line 221 of file DFA.cs.

static short [][] Antlr.Runtime.DFA.UnpackEncodedStringArray

(

string[]

encodedStrings

)

[static]

Definition at line 240 of file DFA.cs.

static char [] Antlr.Runtime.DFA.UnpackEncodedStringToUnsignedChars

(

string

encodedString

)

[static]

Definition at line 247 of file DFA.cs.

int Antlr.Runtime.DFA.SpecialTransition	(	int	state,
		int	symbol
	)

Definition at line 267 of file DFA.cs.

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Member Data Documentation

short [] Antlr.Runtime.DFA.eot [protected]

Definition at line 61 of file DFA.cs.

short [] Antlr.Runtime.DFA.eof [protected]

Definition at line 62 of file DFA.cs.

char [] Antlr.Runtime.DFA.min [protected]

Definition at line 63 of file DFA.cs.

char [] Antlr.Runtime.DFA.max [protected]

Definition at line 64 of file DFA.cs.

short [] Antlr.Runtime.DFA.accept [protected]

Definition at line 65 of file DFA.cs.

short [] Antlr.Runtime.DFA.special [protected]

Definition at line 66 of file DFA.cs.

short [][] Antlr.Runtime.DFA.transition [protected]

Definition at line 67 of file DFA.cs.

int Antlr.Runtime.DFA.decisionNumber [protected]

Definition at line 69 of file DFA.cs.

SpecialStateTransitionHandler Antlr.Runtime.DFA.specialStateTransitionHandler

Definition at line 72 of file DFA.cs.

BaseRecognizer Antlr.Runtime.DFA.recognizer [protected]

Which recognizer encloses this DFA? Needed to check backtracking.

Definition at line 77 of file DFA.cs.

const bool Antlr.Runtime.DFA.debug = false

Definition at line 79 of file DFA.cs.

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Property Documentation

virtual string Antlr.Runtime.DFA.Description [get]

Definition at line 217 of file DFA.cs.

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The documentation for this class was generated from the following file:

• /Users/parrt/antlr/code/antlr/main/runtime/CSharp/Sources/Antlr3.Runtime/Antlr.Runtime/DFA.cs