I am doing something wrong at DrRacket

Question

So I read that DrRacket is a good IDE for common lisp. I downloaded it and have set the language as R5RS and written the following function definition:

(defun f (x)
  (+ 5 5))

However it's returning an error

defun: undefined;
 cannot reference undefined identifier

And I have no clue how to fix it, considering that defun is a well established keyword in common lisp.

Answer 1

DrRacket is NOT an IDE for common lisp. It's an IDE for scheme, which is a Lisp dialect, but different from Common Lisp.

The right syntax for your snippet in scheme would be:

(define (f x)
  (+ 5 5))