11.7 Nonlocal Exits

A nonlocal exit is a transfer of control from one point in a program to another remote point. Nonlocal exits can occur in Emacs Lisp as a result of errors; you can also use them under explicit control. Nonlocal exits unbind all variable bindings made by the constructs being exited.

• Catch and Throw		Nonlocal exits for the program’s own purposes.
• Examples of Catch		Showing how such nonlocal exits can be written.
• Errors		How errors are signaled and handled.
• Cleanups		Arranging to run a cleanup form if an error happens.