Lisp randomize and using two functions to pull from list into another

Question

Okay, so I am new to lisp and i have been working on this program for a couple days getting to know lisp and researching certain parts of lisp such as cons,cdr, let,funcall and

Answer 1

Yes, you do have few argument in your call to cons here:

(defun generate-candy-supply (size)
  (if ( = 0 size)
    (cons (nth( random (length candy-color)) candy-color))
    ;;    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ <= HERE
    (generate-candy-supply ( - size 1))))

cons needs two arguments, when you giving it just one. So with what are you cosing your color?

Also indent your code properly, now it's really difficult to read.

Answer 2

coredump already answered your question.

You can write your code a bit shorter:

(defvar *candy-color*
  #(yellow red blue green pink orange))    ; a vector

(defun generate-candy-supply (size)
  (loop repeat size
        collect (elt *candy-color*
                     (random (length *candy-color*)))))

(defun candy-machine (supply-of-candy)
  (lambda ()
    (pop supply-of-candy)))               ; use POP

Finding wrong number of arguments:

Just compile your code:

[2]> (compile ' generate-candy-supply)
WARNING: in GENERATE-CANDY-SUPPLY : CONS was called with 1 arguments, but it
         requires 2 arguments.

Above warning clearly tells you what is wrong with the code. Since most Common Lisp implementations have one or more compilers, it's useful to actually use them. Depending on the compiler, they can find various problems like wrong argument lists, unused variables, undeclared variables and more.