Re: newbie elisp help ??

[Pascal Bourguignon]

William Case <billlinux@rogers.com> writes:

> Hi;
>
> I am trying to write a function that will insert a line of asterisks+
> spaces across a buffer (as a section divider).  It was started as an
> exercise and has become an exercise in futility.
>
> I am working in the scratch pad using C-j to test the function as it is
> being built.  I have:  (insert "* ").  It returns "* nil". 

Wrong.  (insert "* ") returns just nil, whose textual representation
is inserted by the command bound to C-j.


> Obviously I
> don't want the "nil" to appear.  How do I get rid of it? 

I don't know what command you have bound to C-j.  I use C-x C-e and
C-u C-x C-e to execute forms.   Without C-u, it doesn't print (insert
the textual representation of) the result of the form.


> More importantly to me, how do I get the (insert "* ") command to repeat
> 27 times to give me 54 characters across the buffer?  

Writting a loop!

(require 'cl)                     C-x C-e
(loop repeat 27 do (insert "* ")) C-x C-e

inserts:

* * * * * * * * * * * * * * * * * * * * * * * * * * * 

> I know how to make
> a recursive loop, but it seems to me this is a fairly common challenge
> and there is a probably a function for repetition that I can't find.

How do I make a static mobile?
How do I make a red blue?


> I suppose I am asking for the programming equivalent of 'C-u n'.

I suppose you could read some programming tutorial.  Wouldn't that be a good 
idea?
What about googling for: emacs lisp tutorial


-- 
__Pascal Bourguignon__                     http://www.informatimago.com/

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