Grammar authoring system

A method of building a learned context free grammar (CFG) comprising:

• generating a semantic schema for the learned CFG;
• obtaining a template CFG;
• receiving a training expression;
• providing an annotated expression by annotating the training expression against the semantic schema to provide at least one anchor point that is a known correct alignment between a portion of the training expression and the template CFG;
• parsing the annotated expression to provide a parse result that complies with the anchor point;
• and
• building the learned CFG based on the parse result.

A system for developing a domain-specific, context free grammar (CFG), comprising:

• a template grammar generator receiving a semantic schema and generating a template grammar that inherits the semantic constraints from the semantic schema;
• an annotation interface receiving a user annotation input indicative of a user designated anchor point that is an alignment of at least a portion of a training expression with the semantic schema;
• a parser, coupled to the template grammar generator and the annotation interface, receiving the template grammar and the user annotation input and parsing the training expression to provide a parse result that complies with the anchor points;
• and
• a learner, coupled to the parser, learning the domain-specific CFG based on the parse result.

A method of generating a context free grammar (CFG), comprising:

• generating an underspecified template CFG;
• annotating a training expression, against an abstraction of the template CFG, with one or more anchor points aligning portions of the training expression with preterminals in the CFG;
• parsing the training expression with the template CFG to provide a parse result, given the anchor points;
• learning alignments of the training expression with the template CFG, in addition to the anchor points;
• and
• adding CFG rules to the template CFG to reflect the learned alignment and anchor points.

A method of generating a context free grammar (CFG) for an application in an application domain, comprising:

• generating an underspecified template CFG;
• displaying a schema of the application domain instead of the CFG;
• annotating a training expression against the schema instead of the template CFG, identifying one or more points of alignment between the training expression and the template CFG;
• parsing the training expression with the template CFG to provide a parse result that complies with the points of alignment;
• learning alignments of the training expression with the CFG;
• and
• adding CFG rules to the template CFG to reflect the learning alignments.