A system is defined with a defsystem form in an ordinary Lisp source file. This form must be loaded into the Lisp image in order to define the system in the environment. Once loaded, operations can be carried out on the system by invoking Lisp functions, or, more conveniently, by using the system browser.
For example, the expression:
CL-USER 5 > (compile-system 'debug-app :force t)
would compile every file in a system called
Note: When defining a hierarchy of systems, the leaf systems must be defined first -- that is, a system must be declared before any systems that include it.
By convention, system definitions are placed in a file called
which usually resides in the same directory as the members of the system.
The full syntax of defsystem is given in defsystem. Below is a brief introduction.