schrodinger.application.desmond.antlr3.streams.TokenStream

Class TokenStream

object --+ | IntStream --+ | TokenStream

@brief A stream of tokens accessing tokens from a TokenSource

This is an abstract class that must be implemented by a subclass.

Instance Methods

LT(self, k)
Get Token at current input pointer + i ahead where i=1 is next Token.

get(self, i)
Get a token at an absolute index i; 0..n-1.

getTokenSource(self)
Where is this stream pulling tokens from? This is not the name, but the object that provides Token objects.

toString(self, start=None, stop=None)
Return the text of all tokens from start to stop, inclusive.

Inherited from IntStream: LA, consume, getSourceName, index, mark, release, rewind, seek, size

Inherited from object: __delattr__, __format__, __getattribute__, __hash__, __init__, __new__, __reduce__, __reduce_ex__, __repr__, __setattr__, __sizeof__, __str__, __subclasshook__

Properties

[hide private]

Inherited from object: __class__

LT(self, k)

Get Token at current input pointer + i ahead where i=1 is next Token. i<0 indicates tokens in the past. So -1 is previous token and -2 is two tokens ago. LT(0) is undefined. For i>=n, return Token.EOFToken. Return null for LT(0) and any index that results in an absolute address that is negative.

get(self, i)

Get a token at an absolute index i; 0..n-1. This is really only needed for profiling and debugging and token stream rewriting. If you don't want to buffer up tokens, then this method makes no sense for you. Naturally you can't use the rewrite stream feature. I believe DebugTokenStream can easily be altered to not use this method, removing the dependency.

toString(self, start=None, stop=None)

Return the text of all tokens from start to stop, inclusive. If the stream does not buffer all the tokens then it can just return "" or null; Users should not access $ruleLabel.text in an action of course in that case.

Because the user is not required to use a token with an index stored in it, we must provide a means for two token objects themselves to indicate the start/end location. Most often this will just delegate to the other toString(int,int). This is also parallel with the TreeNodeStream.toString(Object,Object).