Using Medley Interlisp Basics

the parent page has pointers to additional resources. Medley Interlisp also includes an online reference:

  • right-click on the desktop to get to the system menu
  • select DInfo

or, at any prompt, the man command will look up a symbol or phrase in the Interlisp Reference Manual (IRM) and/or the Common Lisp HyperSpec.

Writing a sample Interlisp program

In an (INTERLISP) Exec window, type the following:

(PLUS 1 1)

When you complete typing the ending ) the Interlisp interpreter will perform the calculation and return the result.

One thing you probably noticed, the function name PLUS is capitalized. This is traditional – Interlisp programmers commonly ran with the caps-lock turned on. It’s not that the developers of Interlisp were always shouting at each other. Rather, when Interlisp was developed computer programming was in its early days and all-caps type-in was common. (It’s possible to change the Interlisp exec to automatically capitalize symbols at imput, as is the case with the Common Lisp exec, if that’s your preference.)