Your Wish is My Command

232 Chapter Twelve Training Agents to Recognize Text by Example

short-term memory, they find it difficult to keep track of how abstract con-

cepts map to specific instances when systems grow large. People are simply

much better about thinking about concrete examples than they are about

abstractions such as grammar rules.

Our solution for dealing with the complexity of grammar definition is to

define grammars by

example. The need for a new text pattern will often be-

come apparent to the user when he or she is examining some text that al-

ready contains one or several examples of the pattern. Our approach is to

let the user