own webbased newsgroup types

own webbased newsgroup types

[Stefan Huchler]

I try to write own Group types for some web sites.

But I cant make any sense of old source parts. I am no big lisp
developer yet, but I dont find with google or emacshelp anything about
one thing.


  (let ((last (car (last articles)))
	(did nil)


I have no idea what this "did" thing is supposed to be

found it here:

Http://www.opensource.apple.com/source/emacs/emacs-51/emacs/lisp/gnus/nnslashdot.el

and here:

http://www.mit.edu/~mkgray/stuff/ath/afs/oldfiles/project/silk/root/afs/athena.mit.edu/contrib/xemacs/share/2005-12-08/xemacs-packages/lisp/gnus/nnultimate.el

Re: own webbased newsgroup types

[Helmut Waitzmann]

Stefan Huchler <stefan.huchler@mail.de> writes:

>  (let ((last (car (last articles)))
>	(did nil)
>
>
>I have no idea what this "did" thing is supposed to be

You might read the documentation for the special form "let".  To do
that, type C-h f let RET

Let me comment that documentation:

The first parameter of "let" is the VARLIST, a list of variables.  Each
variable in that VARLIST is either a symbol: SYMBOL, which is bound to
nil, or it is a list of 2 elements: (SYMBOL VALUEFORM), which binds the
SYMBOL to the value of VALUEFORM.

In your example:

>  (let ((last (car (last articles)))
>	(did nil)

the first element of the VARLIST is a list of two elements:

(last (car (last articles)))

= (SYMBOL VALUEFORM)

which tells "let" to bind the SYMBOL "last" to the value of the
VALUEFORM (car (last articles)),

and the second element of the VARLIST is a list of two elements, as well:

(did nil)

= (SYMBOL VALUEFORM)

which tells "let" to bind the SYMBOL "did" to the value of the
VALUEFORM nil.