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Re: question list c

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porinaxel@gmail.com writes:

> struct cell {
>   int val;
>   struct cell * next;
> };
> typedef struct cell cell_t;        <---------- why there is structure cell_t

I don't understand the question.  cell is what is called a struct tag.
It names a structure type, but it must be used with the keyword struct

  struct cell c = { 42, NULL };

and so on.  The author wants to give the type "struct cell" and simpler
name, "cell_t" so one could write

  cell_t c = { 42, NULL };

instead.  It's a common convention to use _t at the end of names that
name types.

> typedef struct cell * list;

Some people don't like hiding the fact that a type is a pointer type
like this.

> int car (list l){
>   if (l) {
>     return (*l).val;
>   }
>   else {
>     return INT_MIN; 
>   }
> }
>
> liste cdr (list l){
>   if (l) {
>     return (* l).next;
>   }
>   else {
>     return (list) 0;
>   }
> }
> int listempty (list l){
>   if (l) {
>     return 0;
>   }
>   else {
>     return 1;
>   }
> }
> int listnonempty (list l){
>   if (l) {
>     return 1;
>   }
>   else {
>     return 0;
>   }
> }

The code won't compile and is very oddly written.  Where is it from?

> i'dont understand any of this function pls help

That's too general a question.  If you ask more specific questions the
question itself will help people to know how to answer.  For example,
"what do all those {}s mean?" and "why is 0 being cast to a pointer
type?" show very different kinds of confusion.

-- 
Ben.

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question list c porinaxel@gmail.com - 2020-03-22 14:16 -0700
  Re: question list c Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-03-22 21:42 +0000
  Re: question list c porinaxel@gmail.com - 2020-03-26 05:40 -0700
    Re: question list c Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-03-26 12:54 +0000
      Re: question list c James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-03-26 09:21 -0400
        Re: question list c Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-03-26 13:33 +0000
      Re: question list c scott@slp53.sl.home (Scott Lurndal) - 2020-03-26 15:23 +0000
        Re: question list c Anton Shepelev <anton.txt@g{oogle}mail.com> - 2020-03-26 19:12 +0300
  Re: question list c mark.bluemel@gmail.com - 2020-03-26 07:27 -0700
    Re: question list c Barry Schwarz <schwarzb@delq.com> - 2020-03-26 07:44 -0700
      Re: question list c scott@slp53.sl.home (Scott Lurndal) - 2020-03-26 15:25 +0000
        Re: question list c chad <cdalten@gmail.com> - 2020-03-26 15:17 -0700
  Re: question list c John Bode <jfbode1029@gmail.com> - 2020-03-26 15:45 -0700
  Re: question list c porinaxel@gmail.com - 2020-03-26 16:28 -0700
    Re: question list c Barry Schwarz <schwarzb@delq.com> - 2020-03-26 16:53 -0700

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