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13 Functions

A Lisp program is composed mainly of Lisp functions. This chapter explains what functions are, how they accept arguments, and how to define them.

• What Is a Function?
• Lambda Expressions
• Naming a Function
• Defining Functions
• Calling Functions
• Mapping Functions
• Anonymous Functions
• Generic Functions
• Accessing Function Cell Contents
• Closures
• Open Closures
• Advising Emacs Lisp Functions
• Declaring Functions Obsolete
• Inline Functions
• The declare Form
• Telling the Compiler that a Function is Defined
• Determining whether a Function is Safe to Call
• Other Topics Related to Functions