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Re: typedef ... refactored

From Anton Shepelev <anton.txt@gmail.com>
Newsgroups comp.lang.c
Subject Re: typedef ... refactored
Date 2020-08-13 00:41 +0300
Organization A noiseless patient Spider
Message-ID <20200813004147.9548ed1e52f166ef19375d8b@gmail.com> (permalink)
References <7a5f16a3-d30d-46ec-9926-b0736428902do@googlegroups.com>

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G G:

> the following comes from "C How to Program"
> by Deitel & Deitel p.501 (refactored somewhat)
>
> struct treeNode
> {
>    struct treeNode *leftPtr;
>    int data; // node value
>    struct treeNode *rightPtr;
>
> }; // end structure treeNode
>
> typedef struct treeNode TreeNode; // synonym for struct treeNode  (1)
>
> typedef TreeNode *TreeNodePtr; // synonym for TreeNode*   (2)
>
> [...]
> question why did the authors use so many typedef(s)?

They used only two. Perhaps it was due a background of an
academic programming language such as Pascal or Modula,
where the idiom is to declare a record type denoted by a
single identifer (no `struct' prefix) and a type of pointer
to that type, e.g. in Pascal:

type PTreeNode = ^TTreeNode; (* forward pointer declaraion *)

     TTreeNode = record
        Left : PTreeNode;
        Data : integer;
        Right: PTreeNode;
     end;

This may explain why they did not mix the struct declaration
and type definition, preferring to do one thing at a time:

typedef struct treeNode
{
   struct treeNode *leftPtr;
   int data; // node value
   struct treeNode *rightPtr;

} TreeNode;

I can't blame them for missing the perspicuity of Pascal.
Notice also the graphical-symmetrical layout of the
structure, as if the author(s) had a predominantly visual
thinking. In my opinion, it a sin, and the members should
grouped by the principle of cohesion, accoridng to their
nature.

But why the illiterate title: "C How to Program", I truly
cannot conjecture. Maybe Yoda was chief editor...

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typedef ... refactored G G <gdotone@gmail.com> - 2020-08-09 01:07 -0700
  Re: typedef ... refactored G G <gdotone@gmail.com> - 2020-08-09 01:46 -0700
    Re: typedef ... refactored Richard Damon <Richard@Damon-Family.org> - 2020-08-09 08:09 -0400
      Re: typedef ... refactored Manfred <noname@add.invalid> - 2020-08-09 18:08 +0200
  Re: typedef ... refactored Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-08-09 09:29 +0000
  Re: typedef ... refactored Johann Klammer <klammerj@NOSPAM.a1.net> - 2020-08-09 13:29 +0200
  Re: typedef ... refactored Bonita Montero <Bonita.Montero@gmail.com> - 2020-08-09 13:53 +0200
    Re: typedef ... refactored Poprocks <please@replytogroup.com> - 2020-08-10 20:37 +0000
      Re: typedef ... refactored Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-08-10 13:49 -0700
        Re: typedef ... refactored Poprocks <please@replytogroup.com> - 2020-08-10 23:09 +0000
          Re: typedef ... refactored Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-08-11 07:14 +0000
            Why not indeed??? (Was: typedef ... refactored) gazelle@shell.xmission.com (Kenny McCormack) - 2020-08-11 07:48 +0000
            Re: typedef ... refactored Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-08-11 10:56 +0100
      Re: typedef ... refactored Bonita Montero <Bonita.Montero@gmail.com> - 2020-08-11 08:10 +0200
        Re: typedef ... refactored Anton Shepelev <anton.txt@gmail.com> - 2020-08-13 00:52 +0300
          Re: typedef ... refactored Bonita Montero <Bonita.Montero@gmail.com> - 2020-08-14 14:13 +0200
            Re: typedef ... refactored Bart <bc@freeuk.com> - 2020-08-14 13:37 +0100
              Re: typedef ... refactored Bonita Montero <Bonita.Montero@gmail.com> - 2020-08-14 14:54 +0200
                Re: typedef ... refactored David Brown <david.brown@hesbynett.no> - 2020-08-14 16:46 +0200
                Re: typedef ... refactored Bart <bc@freeuk.com> - 2020-08-14 16:59 +0100
                Re: typedef ... refactored David Brown <david.brown@hesbynett.no> - 2020-08-14 21:05 +0200
                Re: typedef ... refactored Bart <bc@freeuk.com> - 2020-08-14 20:51 +0100
                Re: typedef ... refactored antispam@math.uni.wroc.pl - 2020-08-16 13:36 +0000
                Re: typedef ... refactored Bart <bc@freeuk.com> - 2020-08-16 15:58 +0100
                Re: typedef ... refactored antispam@math.uni.wroc.pl - 2020-08-16 18:10 +0000
                Re: typedef ... refactored Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-08-14 13:23 -0700
                Re: typedef ... refactored David Brown <david.brown@hesbynett.no> - 2020-08-16 19:48 +0200
                [OT] words.  Was: typedef ... refactored Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-08-16 20:08 +0100
                Re: [OT] words. Was: typedef ... refactored David Brown <david.brown@hesbynett.no> - 2020-08-17 10:50 +0200
                Re: [OT] words. Was: typedef ... refactored Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-08-17 12:00 +0100
                Re: typedef ... refactored Anton Shepelev <anton.txt@g{oogle}mail.com> - 2020-08-17 17:51 +0300
                Re: typedef ... refactored Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-08-17 16:06 +0100
                Re: typedef ... refactored Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-08-17 10:48 -0700
                Re: typedef ... refactored scott@slp53.sl.home (Scott Lurndal) - 2020-08-17 19:36 +0000
                Re: typedef ... refactored Siri Cruise <chine.bleu@yahoo.com> - 2020-08-17 14:06 -0700
                Re: typedef ... refactored Bonita Montero <Bonita.Montero@gmail.com> - 2020-08-14 18:37 +0200
                Re: typedef ... refactored Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-08-14 10:29 -0700
                Re: typedef ... refactored David Brown <david.brown@hesbynett.no> - 2020-08-14 21:10 +0200
                Re: typedef ... refactored Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-08-14 12:32 -0700
  Re: typedef ... refactored G G <gdotone@gmail.com> - 2020-08-09 05:44 -0700
    Re: typedef ... refactored Barry Schwarz <schwarzb@delq.com> - 2020-08-09 08:12 -0700
      Re: typedef ... refactored G G <gdotone@gmail.com> - 2020-08-09 08:32 -0700
  Re: typedef ... refactored John Bode <jfbode1029@gmail.com> - 2020-08-12 11:45 -0700
    Re: typedef ... refactored Bart <bc@freeuk.com> - 2020-08-12 19:59 +0100
    Re: typedef ... refactored Siri Cruise <chine.bleu@yahoo.com> - 2020-08-12 14:16 -0700
  Re: typedef ... refactored Anton Shepelev <anton.txt@gmail.com> - 2020-08-13 00:41 +0300

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