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Re: flowto (Just for fun)

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Nick Keighley <nick_keighley_nospam@hotmail.com> writes:

> On Jul 10, 12:15 pm, Dr Nick <3-nos...@temporary-address.org.uk>
> wrote:
>> If it's small and local and never used anywhere else then you might as
>> well just have it as an explicit naked value (with an explanatory
>> comment) rather than carefully creating an enum just to give it a name
>> for a one-off use right next to where it's defined.
>
> I think that's a mistake. If you're going to create a symbolic
> constant if you use it twice why not do it when you use it once. The
> same arguemtn applies to functions. Soem people use the rule "only
> create a function if it used more that once" and then up with monsters
>
> The same number can have many meanings in the same program
>
>     base_station[9].port[9] = 9;   /* write a tab to the control port
> of the last basestation */

I'm not entirely convinced that
    enum {last_basestation=9};
    enum (control_port=9};
    enum {tab=9};
    base_station[last_basestation].port[control_port] = tab;
is a lot clearer!

I think this is a different argument to avoiding putting a tidy piece of
code into a function.

I don't like the enum hack.  If you also don't want to deal with the
scope issues of #defines you don't have much choice.

But it's not clear-cut.  There's almost certainly a time and place for
all of them.  

I'd be a lot more sympathetic to:
    enum {main_basestation=9,sub_basestation=10};
    enum (control_port=9,display_port=17};
    enum {backspace=8,tab=9};
    base_station[main_basestation].port[control_port] = tab;
    base_station[sub_basestation].port[display_port] = backspace;

although I'd probably rewrite the enum names to put the common part
first (given that enums don't have a very good namespace).
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Re: flowto (Just for fun) luser- -droog <mijoryx@yahoo.com> - 2011-07-07 00:03 -0700
  Re: flowto (Just for fun) Dr Nick <3-nospam@temporary-address.org.uk> - 2011-07-07 08:06 +0100
    Re: flowto (Just for fun) Shao Miller <sha0.miller@gmail.com> - 2011-07-07 19:34 -0400
    Re: flowto (Just for fun) Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-07-08 02:39 +0300
      Re: flowto (Just for fun) Keith Thompson <kst-u@mib.org> - 2011-07-07 17:09 -0700
      Re: flowto (Just for fun) gwowen <gwowen@gmail.com> - 2011-07-08 03:10 -0700
        Re: flowto (Just for fun) Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-07-10 04:44 +0300
          Re: flowto (Just for fun) Ike Naar <ike@sverige.freeshell.org> - 2011-07-10 08:51 +0000
            Re: flowto (Just for fun) Dr Nick <3-nospam@temporary-address.org.uk> - 2011-07-10 10:52 +0100
              Re: flowto (Just for fun) Ike Naar <ike@sverige.freeshell.org> - 2011-07-10 11:12 +0000
                Re: flowto (Just for fun) Dr Nick <3-nospam@temporary-address.org.uk> - 2011-07-10 12:15 +0100
                Re: flowto (Just for fun) Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-07-11 03:32 -0700
                Re: flowto (Just for fun) Dr Nick <3-nospam@temporary-address.org.uk> - 2011-07-11 20:11 +0100
            Re: flowto (Just for fun) Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-07-10 20:42 +0300
            Re: flowto (Just for fun) "io_x" <a@b.c.invalid> - 2011-07-11 08:08 +0200
    Re: flowto (Just for fun) luser- -droog <mijoryx@yahoo.com> - 2011-07-10 23:51 -0700
      Re: flowto (Just for fun) "io_x" <a@b.c.invalid> - 2011-07-11 09:15 +0200
  Re: flowto (Just for fun) "io_x" <a@b.c.invalid> - 2011-07-08 20:06 +0200

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