This chapter describes the debugging facilities that are available in development systems. The purpose of these facilities is to provide information concerning the control flow of your program.
The main features of the debugging package are as follows:
The Procedure Box model of execution is also called the Byrd Box model after its inventor, Lawrence Byrd.
Much of the information in this chapter is also in Chapter eight of [Clocksin & Mellish 81], which is recommended as an introduction.
Unless otherwise stated, the debugger prints goals using
write_term/3 with the value of the Prolog flag
The debugger is not available in runtime systems and the predicates defined in this chapter are undefined; see Runtime Systems.
|• Procedure Box
|The Procedure Box Control Flow Model
|• Basic Debug
|Basic Debugging Predicates
|• Plain Spypoint
|• Debug Format
|Format of Debugging Messages
|• Debug Commands
|Commands Available during Debugging
|• Advanced Debugging
|Advanced Debugging — an Introduction
|• Breakpoint Predicates
|Breakpoint Handling Predicates
|• Breakpoint Processing
|The Processing of Breakpoints
|• Breakpoint Conditions
|Consulting during Debugging
|• Exceptions Debug
|• Debug Summary