antlr.debug

Class ParseTreeDebugParser

public class ParseTreeDebugParser extends LLkParser

Override the standard matching and rule entry/exit routines to build parse trees. This class is useful for 2.7.3 where you can specify a superclass like class TinyCParser extends Parser(ParseTreeDebugParser);

Field Summary
protected Stack	currentParseTreeRoot Each new rule invocation must have it's own subtree.
protected ParseTreeRule	mostRecentParseTreeRoot Track most recently created parse subtree so that when parsing is finished, we can get to the root.
protected int	numberOfDerivationSteps For every rule replacement with a production, we bump up count.

Constructor Summary
	ParseTreeDebugParser(int k_)
	ParseTreeDebugParser(ParserSharedInputState state, int k_)
	ParseTreeDebugParser(TokenBuffer tokenBuf, int k_)
	ParseTreeDebugParser(TokenStream lexer, int k_)

Method Summary
protected void	addCurrentTokenToParseTree() This adds LT(1) to the current parse subtree.
int	getNumberOfDerivationSteps()
ParseTree	getParseTree()
void	match(int i)
void	match(BitSet bitSet)
void	matchNot(int i)
void	traceIn(String s) Create a rule node, add to current tree, and make it current root
void	traceOut(String s) Pop current root; back to adding to old root

Field Detail

currentParseTreeRoot

protected Stack currentParseTreeRoot

Each new rule invocation must have it's own subtree. Tokens are added to the current root so we must have a stack of subtree roots.

mostRecentParseTreeRoot

protected ParseTreeRule mostRecentParseTreeRoot

Track most recently created parse subtree so that when parsing is finished, we can get to the root.

numberOfDerivationSteps

protected int numberOfDerivationSteps

For every rule replacement with a production, we bump up count.

Constructor Detail

ParseTreeDebugParser

public ParseTreeDebugParser(int k_)

ParseTreeDebugParser

public ParseTreeDebugParser(ParserSharedInputState state, int k_)

ParseTreeDebugParser

public ParseTreeDebugParser(TokenBuffer tokenBuf, int k_)

ParseTreeDebugParser

public ParseTreeDebugParser(TokenStream lexer, int k_)

Method Detail

addCurrentTokenToParseTree

protected void addCurrentTokenToParseTree()

This adds LT(1) to the current parse subtree. Note that the match() routines add the node before checking for correct match. This means that, upon mismatched token, there will a token node in the tree corresponding to where that token was expected. For no viable alternative errors, no node will be in the tree as nothing was matched() (the lookahead failed to predict an alternative).