22.4 Edebug

Edebug is a source-level debugger for SXEmacs and XEmacs Lisp programs that provides the following features:

• Step through evaluation, stopping before and after each expression.
• Set conditional or unconditional breakpoints, install embedded breakpoints, or a global break event.
• Trace slow or fast stopping briefly at each stop point, or each breakpoint.
• Display expression results and evaluate expressions as if outside of Edebug. Interface with the custom printing package for printing circular structures.
• Automatically reevaluate a list of expressions and display their results each time Edebug updates the display.
• Output trace info on function enter and exit.
• Errors stop before the source causing the error.
• Display backtrace without Edebug calls.
• Allow specification of argument evaluation for macros and defining forms.
• Provide rudimentary coverage testing and display of frequency counts.

The first three sections should tell you enough about Edebug to enable you to use it.

• Using Edebug: Introduction to use of Edebug.
• Instrumenting: You must first instrument code.
• Edebug Execution Modes: Execution modes, stopping more or less often.
• Jumping: Commands to jump to a specified place.
• Edebug Misc: Miscellaneous commands.
• Breakpoints: Setting breakpoints to make the program stop.
• Trapping Errors: trapping errors with Edebug.
• Edebug Views: Views inside and outside of Edebug.
• Edebug Eval: Evaluating expressions within Edebug.
• Eval List: Automatic expression evaluation.
• Reading in Edebug: Customization of reading.
• Printing in Edebug: Customization of printing.
• Tracing: How to produce tracing output.
• Coverage Testing: How to test evaluation coverage.
• The Outside Context: Data that Edebug saves and restores.
• Instrumenting Macro Calls: Specifying how to handle macro calls.
• Edebug Options: Option variables for customizing Edebug.