Package fido.grammar

The Fido system uses a grammatical system called link grammar to identify relationships between words in the user command.

See:
Description

Interface Summary

Expression

Super interface for NodeExpression and AlwaysExpression.

Class Summary

AlwaysExpression	The special node for a grammar string is a compliment for an optional expressionn.
Grammar	The Fido system uses a grammatical system called link grammar to identify relationships between words in the user command.
GrammarStack	Each SentenceThread contains a GrammarStack that is used to push and pop StackElements.
Link	A Link represents the grammatical relationship between two words.
NodeExpression	The basic component for a grammar string.
SentenceThread	Represents one possible linkage the grammar has found during incremental processing.
SentenceThreadFactory	Factory pattern class to create a new SentenceThread or clone an existing one.
StackElement	Represents all of the grammar expressions for a word.

Exception Summary

GrammarParseException

Thrown by Grammar classes when the grammar string for the word in the dataserver contains an invalid string that cannot be parsed.

Package fido.grammar Description

The Fido system uses a grammatical system called link grammar to identify relationships between words in the user command. The command is defined as a set of words, which is the terminal symbols of the grammar, each of which has a linking requirement. A sequence of words is defined as a successful sentence if:

• all of the non-optional linking requirements for all of the words are satisfied
• arcs drawn connecting related words do not cross
• the links connect all of the words in the sequence together
• no two links connect the same words

The linking requirements are passed into the module via Word Sense of a Word Package. Each Word Sense in the Word Package contains a Grammar String, the linking requirement, and a pointer to the node in the hierarchy. Each Grammar String is a list of connectors joined by boolean operators and and or. Also some connectors can have multiple connectors connect to it, and some connectors can be optional.

The output of the Grammar module is a Vector of links. A link is a class that represents a relationship between two Word Senses. The input to the module is a list of Word Packages, but the output links reference only one of the Word Senses in the package. Therefore, if a word has multiple senses (meanings) in the dictionary, the Grammar module will pick one, and only one, meaning of the word to pass to the next module.