4 Recursive Transition Networks (RTNs)

This lecture has three main goals:

1. To explain what Recursive Transition Networks (RTNs) are, and in particular to explain the role stacks play in controlling their behavior.

2. To show that RTNs are genuinely more powerful than FSAs, and to briefly discuss the link between RTNs and context free grammars.

3. To show how to extend our previous work on FSA recognizers to obtain a simple RTN recognizer in Prolog.

• 4.1 From FSAs to RTNs

• 4.2 A Closer Look
  • 4.2.1 Stacks
  • 4.2.2 Stacks and RTNs
  • 4.2.3 An Example

• 4.3 Theoretical Remarks

• 4.4 Putting it in Prolog

• 4.5 Exercises