12.1 Introduction

The Tracer tool is a debugging aid which gives you an interface to the LispWorks trace facilities. These allow you to follow the execution of particular functions and help you identify where errors occur during execution.

To create a Tracer, choose Window > Tools > Tracer or click in the LispWorks toolbar. Alternatively, a tracer can be created or displayed from within many other tools by choosing the command Trace > Show in Tracer in any menu whose commands operate on a traceable symbol.

The Tracer has three views:

• The Trace State view allows you to trace and untrace functions and change trace options for each function.
• The Output Data view records all tracing events in a tree structure and allows you to examine the arguments and results of each function call.
• The Output Text view shows all tracing events in textual format.