Overview

The AutoLISP examples that I gave you in Chapter 8, AutoLISP by Example: Getting Started, were simplified, but that doesn t mean they weren t useful. In fact, with only those examples, you can now create hundreds of new and useful AutoCAD commands. But before long, you ll probably want to generate functions that require something more complex than the skeletal AutoLISP structure laid out in the previous chapter. This chapter adds some meat to that skeleton, not only by introducing you to more complex functions, but also by describing two of the most important concepts for your future programming efforts: error handling and annotating.

First, though, let s try to preempt the frustration inherent in creating your own programs. When your program fails to work, how do you figure out what s wrong?

• Debugging Techniques

• Error Handling

• Annotation

• Selection Sets

• IF Function

• WHILE Function

• COND, INITGET, and GETKWORD Functions

• Text and String Manipulation

• Getting to DOS