Print something in file

hello everyone,

I want to do this in lisp :

<code> <tab> <the true char> <tab> <In lisp representation >
65 . A . #\A
66 . B . #\B
67 . C . #\C
68 . D . #\D
69 . E . #\E
70 . F . #\F


And I want to put this into a file.

Behold what I tried to do:

(defun alpha(a b f)
(setq file(open f :direction :output))
(loop
(cond
((equal a b)(return))
((print (code-char a)file)(incf a))
)))

This program is supposed to print all charcteres between a and b. And to put them into a file f.
For exemple, for (alpha 65 70 file), I'am suppose to get what I wrote before :

<code> <une tabulation> <the true char> <tab><In lisp representation >
65 . A . #\A
66 . B . #\B
67 . C . #\C
68 . D . #\D
69 . E . #\E
70 . F . #\F

I know that program alpha is false. Maybe I have to do something like this :

(print (string-concat  a (code-char 9)(string(code-char a) (code-char a)))

But string concat send me a an error with a because it's not a string.
I don't know if you understand what I want to do, but all your help is needed !!!

Sorry for my english, I am actually french so ...

Thank you.

alcibiade123 wrote:hello everyone,

I want to do this in lisp :

<code> <tab> <the true char> <tab> <In lisp representation >
65 . A . #\A
66 . B . #\B
67 . C . #\C
68 . D . #\D
69 . E . #\E
70 . F . #\F


And I want to put this into a file.

Behold what I tried to do:

(defun alpha(a b f)
(setq file(open f :direction :output))
(loop
(cond
((equal a b)(return))
((print (code-char a)file)(incf a))
)))

This program is supposed to print all charcteres between a and b. And to put them into a file f.
For exemple, for (alpha 65 70 file), I'am suppose to get what I wrote before :

<code> <une tabulation> <the true char> <tab><In lisp representation >
65 . A . #\A
66 . B . #\B
67 . C . #\C
68 . D . #\D
69 . E . #\E
70 . F . #\F

I know that program alpha is false. Maybe I have to do something like this :

(print (string-concat  a (code-char 9)(string(code-char a) (code-char a)))

But string concat send me a an error with a because it's not a string.
I don't know if you understand what I want to do, but all your help is needed !!!

Sorry for my english, I am actually french so ...

Thank you.

Do you want to print out the whole table, or only the characters?

Hints: lookup the syntax of LOOP and FORMAT (and then use FORMAT instead of PRINT)

See also from Practical Common Lisp:

• Chapter 7 - Macros: Standard Control Constructs - i.e. the section about LOOP
• Chapter 18 - A Few FORMAT Recipes

If you feel adventurous read also:

• Chapter 22 - LOOP for Black Belts

Happy Lisp hacking...

- edgar

Hi everyone,

Thank you for your answer, behold what I found :

(defun alphabet (a b)(setq b (+ b 1))
(loop
(cond
((equal a b)(return))
((princ a)(princ #\tab)(princ(code-char a))(princ #\tab)(prin1 (code-char a))(terpri)(incf a))
)))

With this function I have exacty what I wanted :

(alphabet 65 70)

65 A #\A
66 B #\B
67 C #\C
68 D #\D
69 E #\E
70 F #\F

But I always want to put this result into a file...
To write something into a file I found this on my course :

(setq file(open "file" :direction :output))

So I did this :

(print "dodo" file)
"dodo"

The file is created but if I do more file in my prompt, I have nothing.

more file
>
I don't know why it doesn't work ...
I wanted to use this method to put "alphabet" into a file but like "dodo" I have nothing into my file.

Sorry for my english.. again

@Indecipherable

Yes I want to print the whole table.

(defun tabulate-characters (a b &optional (out *standard-output*))
  (loop for cc from a below b
        do (format out "~D~C~A~C#\\~:C~%"
                   cc
                   #\Tab
                   (code-char cc)
                   #\Tab
                   (code-char cc))))

(defun print-characters (a b dest)
  (with-open-file (d dest
                     :direction :output
                     :if-exists :supersede
                     :if-does-not-exist :create)
    (tabulate-characters a b d)))

Note that the #\Tab character is semi-standard.

Cheers
--
MA

Thank you marcoxa, your solution works very well.
But can you tell me why my function didn't work ? I mean for the (setq file(open "file" :direction : output)) Because when I tried to adapt my function to yours with this :

(defun  alphabet (a b &optional (out *standard-output*))
   (setq b (+ b 1))
       (loop                 
             (cond             
                     ((equal a b)(return))
                     ((princ a)(princ #\tab)(princ(code-char a))(princ #\tab)(prin1 (code-char a))(terpri)(incf a))
              )
       )
)
(setq file(open "file" :direction :output))
    (defun print-characters (a b dest)
          (with-open-file(d dest
                                          :direction :output
                                          :if-exists :supersede 
                                          :if-does-not-exist :create)                                                                   
                                          (alphabet a b d)))

It didn't work. So why ???
Can somebody please tell me why ? It's realy important for me to understand my mistakes.

Well. We have to figure out *where* and *how* it did not work. To begin with, you are not passing the output stream to your output functions (PRINC and PRIN1).

MA

Two consistent problems in your code are that you're using setq where you should be using let, and that you're using C-style parenthesis closing instead of lisp-style. The latter issue is just a stylistic one, but it does make it harder for us to read your code.
I think you should also re-read the documentation for with-open-file, because (setq file(open "file" :direction :output)) is unnecessary.

After that, it would probably help if you reasoned through your code, describing to yourself exactly what you expect to happen and why. I find this very useful myself, because it often shows exactly where I've gone wrong.

another solution:

(defun alpha (start end fname)
  (with-open-file (*standard-output*
                   fname
                   :direction :output
                   :if-exists :supersede)
                  (loop for i from start to end
                        do (format t "~{~a~4t~a~4t~a~%~}" (list i
                                                                (code-char i)
                                                                (prin1-to-string (code-char i)))))))