Re: why do some writers declare and define variables separately

From	Jens Schmidt <Jens.Schmidt-HH@gmx.de>
Newsgroups	comp.lang.c
Subject	Re: why do some writers declare and define variables separately
Date	2013-09-19 01:19 +0200
Organization	at home
Message-ID	<b9uqnkF7dvbU1@mid.uni-berlin.de> (permalink)
References	<clcm-20130918-0002@plethora.net>

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yoodavid wrote:

> Can anyone tell me why some writers decide to declare and 
> write definitions for variables separately, rather than 
> together?

Your code doesn't have any separate declaration. What is separate are
definition and initialisation. A declaration would be e.g. a line
  extern int definelater;
at the very begining.

As I can't read the mind of "some writers", here are some guesses:
Early versions of C didn't have the possibility to define variables
everywhere in a function. You had to first define or declare all names
used in the function and only then start with statements.
Complex types, i.e. struct and union types, are not always initializeable
inside the definition. So you have to initialize in separate statements.
Now the programmer initialiazes everything this way for consistency.
I'd categorize that as marginally valid at its time, but obsolete with
modern usage.

> wouldn't the later reduce code lines? 

Reduction of code lines a non-relevant argument nowadays. The most expensive
resource in computing is the programmer. So the criteria for coding style
are a) is it clearly visible from the source code, what the intention was
and b) is it improbable to introduce errors, especially later when changing
the code.
Actually the result is the same: initialize as soon after definition.
-- 
Greetings,
  Jens Schmidt

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why do some writers declare and define variables separately yoodavid <odimegwudavid@yahoo.fr> - 2013-09-18 16:42 -0500
  Re: why do some writers declare and define variables separately Fred K <fred.l.kleinschmidt@gmail.com> - 2013-09-18 14:52 -0700
  Re: why do some writers declare and define variables separately Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-09-18 18:08 -0400
  Re: why do some writers declare and define variables separately T0xicCode <T0xic@co.de> - 2013-09-18 18:10 -0400
    Re: why do some writers declare and define variables separately Ken Brody <kenbrody@spamcop.net> - 2013-09-19 11:16 -0400
      Re: why do some writers declare and define variables separately T0xicCode <T0xic@co.de> - 2013-09-19 11:45 -0400
  Re: why do some writers declare and define variables separately Keith Thompson <kst-u@mib.org> - 2013-09-18 15:45 -0700
  Re: why do some writers declare and define variables separately Jens Schmidt <Jens.Schmidt-HH@gmx.de> - 2013-09-19 01:19 +0200
  Re: why do some writers declare and define variables separately Francis Glassborow <francis.glassborow@btinternet.com> - 2013-09-19 02:13 +0100
    Re: why do some writers declare and define variables separately Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-09-19 03:59 +0100
      Re: why do some writers declare and define variables separately Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2013-09-27 00:49 +0300
      Re: why do some writers declare and define variables separately Anand Hariharan <mailto.anand.hariharan@gmail.com> - 2013-10-03 15:41 -0700
        Re: why do some writers declare and define variables separately Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-10-04 00:42 +0100
    Re: why do some writers declare and define variables separately Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-09-19 00:01 -0400
      Re: why do some writers declare and define variables separately David Brown <david@westcontrol.removethisbit.com> - 2013-09-19 10:17 +0200
      Re: why do some writers declare and define variables separately "osmium" <r124c4u102@comcast.net> - 2013-09-19 06:44 -0500
      Re: why do some writers declare and define variables separately Les Cargill <lcargill99@comcast.com> - 2013-09-19 08:00 -0500
        Re: why do some writers declare and define variables separately Noob <root@127.0.0.1> - 2013-09-19 15:12 +0200
        Re: why do some writers declare and define variables separately Keith Thompson <kst-u@mib.org> - 2013-09-19 08:31 -0700
          Re: why do some writers declare and define variables separately Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-09-19 11:35 -0400
            Re: why do some writers declare and define variables separately Keith Thompson <kst-u@mib.org> - 2013-09-19 12:16 -0700
              Re: why do some writers declare and define variables separately Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-09-19 15:32 -0400
                Re: why do some writers declare and define variables separately Tim Rentsch <txr@alumni.caltech.edu> - 2013-09-22 12:36 -0700
        Re: why do some writers declare and define variables separately Tim Rentsch <txr@alumni.caltech.edu> - 2013-09-22 11:28 -0700
          Re: why do some writers declare and define variables separately Öö Tiib <ootiib@hot.ee> - 2013-09-23 03:26 -0700
            Re: why do some writers declare and define variables separately Tim Rentsch <txr@alumni.caltech.edu> - 2013-09-24 20:33 -0700
              Re: why do some writers declare and define variables separately Öö Tiib <ootiib@hot.ee> - 2013-09-25 04:37 -0700
              Re: why do some writers declare and define variables separately Keith Thompson <kst-u@mib.org> - 2013-09-25 08:24 -0700
                Re: why do some writers declare and define variables separately glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2013-09-25 19:08 +0000
          Re: why do some writers declare and define variables separately Les Cargill <lcargill99@comcast.com> - 2013-09-25 17:37 -0500
    Re: why do some writers declare and define variables separately Tim Rentsch <txr@alumni.caltech.edu> - 2013-09-22 11:34 -0700
  Re: why do some writers declare and define variables separately gordonb.t5wsh@burditt.org (Gordon Burditt) - 2013-09-25 05:29 -0500
    Re: why do some writers declare and define variables separately Ian Collins <ian-news@hotmail.com> - 2013-09-25 22:35 +1200
      Re: why do some writers declare and define variables separately David Brown <david@westcontrol.removethisbit.com> - 2013-09-25 13:02 +0200
      Re: why do some writers declare and define variables separately James Kuyper <jameskuyper@verizon.net> - 2013-09-25 08:39 -0400
        Re: why do some writers declare and define variables separately Keith Thompson <kst-u@mib.org> - 2013-09-25 08:23 -0700
        Re: why do some writers declare and define variables separately Ian Collins <ian-news@hotmail.com> - 2013-09-26 08:06 +1200
          Re: why do some writers declare and define variables separately James Kuyper <jameskuyper@verizon.net> - 2013-09-25 16:38 -0400
            Re: why do some writers declare and define variables separately Ian Collins <ian-news@hotmail.com> - 2013-09-26 09:17 +1200
              Re: why do some writers declare and define variables separately Öö Tiib <ootiib@hot.ee> - 2013-09-25 14:32 -0700
                Re: why do some writers declare and define variables separately Ian Collins <ian-news@hotmail.com> - 2013-09-26 09:50 +1200
              Re: why do some writers declare and define variables separately Ian Collins <ian-news@hotmail.com> - 2013-09-26 09:55 +1200
              Re: why do some writers declare and define variables separately James Kuyper <jameskuyper@verizon.net> - 2013-09-25 18:50 -0400
                Re: why do some writers declare and define variables separately Ian Collins <ian-news@hotmail.com> - 2013-09-26 11:17 +1200
                Re: why do some writers declare and define variables separately James Kuyper <jameskuyper@verizon.net> - 2013-09-25 21:26 -0400
                Re: why do some writers declare and define variables separately Ian Collins <ian-news@hotmail.com> - 2013-09-26 13:50 +1200
      Re: why do some writers declare and define variables separately Noob <root@127.0.0.1> - 2013-09-25 15:55 +0200
        Re: why do some writers declare and define variables separately James Kuyper <jameskuyper@verizon.net> - 2013-09-25 10:03 -0400
          Re: why do some writers declare and define variables separately Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2013-09-27 01:29 +0300
      Re: why do some writers declare and define variables separately Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2013-09-27 01:20 +0300
    Re: why do some writers declare and define variables separately David Brown <david@westcontrol.removethisbit.com> - 2013-09-25 13:05 +0200
      Re: why do some writers declare and define variables separately Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-09-25 23:01 +0100
        Re: why do some writers declare and define variables separately James Kuyper <jameskuyper@verizon.net> - 2013-09-25 18:56 -0400
          Re: why do some writers declare and define variables separately David Brown <david@westcontrol.removethisbit.com> - 2013-09-26 09:10 +0200
            Re: why do some writers declare and define variables separately James Kuyper <jameskuyper@verizon.net> - 2013-09-26 07:31 -0400
              Re: why do some writers declare and define variables separately David Brown <david@westcontrol.removethisbit.com> - 2013-09-26 13:58 +0200
                Re: why do some writers declare and define variables separately James Kuyper <jameskuyper@verizon.net> - 2013-09-26 09:12 -0400
  Re: why do some writers declare and define variables separately Michael Lenz <unrest@nullvector.org> - 2013-10-03 19:06 +0000
    Re: why do some writers declare and define variables separately James Kuyper <jameskuyper@verizon.net> - 2013-10-03 15:26 -0400
  Re: why do some writers declare and define variables separately Dag-Erling Smørgrav <des@des.no> - 2013-10-03 21:15 +0200

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