LispForum

Posted: **Thu Sep 16, 2010 6:19 pm**

Hello all,
I'm trying to write a simple program, but I can't seem to get around the fact that (format) returns NIL. Therefore my program output always looks like this:

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Welcome. Please enter your name.
NILwinifred

...as opposed to what I'd like, which is this:

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Welcome. Please enter your name.
winifred

I know that this is a very basic question, but every time I Google "lisp format nil" or any combination thereof (believe me, I've probably tried them all) it comes up with every Lisp program out there, because they all use (format) and NIL!\
Thank you so much for your help.
~RAM

Posted: **Thu Sep 16, 2010 7:50 pm**

Could you post the relevant snippet of your code? I don't remember seeing this problem.

Maybe this example will help?

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(defun read-name ()
  (format t "Welcome. Please enter your name.~%")
  (read-line))

Posted: **Thu Sep 16, 2010 8:09 pm**

I see how your program works, and I'll modify mine to be more like that, perhaps having the user enter symbols instead of functions.

Here's my code in case you're curious though. "phrases.txt" is one big long parenthesized list of sayings.

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(progn
(setq list (read (open "phrases.txt")))
(defun ok () (format t "~A." (nth (random (length list)) list)))
(format t "Welcome to Fortune Teller.~%Type (ok) for a fortune or (bye) to exit.~%")
(loop (print (eval (read)))))

Posted: **Fri Sep 17, 2010 10:17 pm**

Okay, I feel really foolish. The (print) statement... yeah... Case closed, sorry everybody *facepalm*

Posted: **Sat Sep 18, 2010 6:02 am**

No problem. As long as you're willing to learn, we're here to help.

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