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Re: Comparison Style

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Date Thu, 25 Apr 2013 23:43:08 -0400
From Dave Angel <davea@davea.name>
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Subject Re: Comparison Style
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On 04/25/2013 10:48 PM, Chris Angelico wrote:

     <SNIP>

> Also, this protection helps only when the "constant"
> is actually something the compiler knows is a constant - it doesn't
> work in a search function, for instance:
>
> char *strchr(char *string, char findme) {
>      while (*string) {
>          if (*string==findme) return string;
>          ++string;
>      }
>      return 0;
> }

Sure, but if I were coding in C again, I'd have made that function signature

char *strchr(char *string, const char findme) {
    or maybe
char *strchr(const char *string, const char findme) {

>
> If you switch the order of operands in that, the compiler won't help
> you.

Yes, it would.

> Plus it "reads" wrong. So the convention is still
> variable==constant.

In my case, after having it drilled in that you're "supposed" to put the 
constant first, I realized that I never had any problem with using =, 
because as soon as I questioned the order, I just double-checked that I 
was using ==.  At that point, there was no longer any benefit to making 
the order backwards.


-- 
DaveA

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Thread

Comparison Style llanitedave <llanitedave@veawb.coop> - 2013-04-24 22:49 -0700
  Re: Comparison Style Chris Angelico <rosuav@gmail.com> - 2013-04-25 15:57 +1000
    Re: Comparison Style llanitedave <llanitedave@veawb.coop> - 2013-04-25 07:19 -0700
      Re: Comparison Style Chris Angelico <rosuav@gmail.com> - 2013-04-26 02:25 +1000
      Re: Comparison Style Steve Simmons <square.steve@gmail.com> - 2013-04-25 19:31 +0100
        Re: Comparison Style llanitedave <llanitedave@veawb.coop> - 2013-04-25 13:13 -0700
          Re: Comparison Style Neil Cerutti <neilc@norwich.edu> - 2013-04-25 20:15 +0000
          Re: Comparison Style Steve Simmons <square.steve@gmail.com> - 2013-04-25 21:35 +0100
          Re: Comparison Style Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-04-26 10:02 +0100
  Re: Comparison Style Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-04-25 22:37 -0400
  Re: Comparison Style Chris Angelico <rosuav@gmail.com> - 2013-04-26 12:48 +1000
    Re: Comparison Style Roy Smith <roy@panix.com> - 2013-04-27 17:03 -0400
      Re: Comparison Style Terry Jan Reedy <tjreedy@udel.edu> - 2013-04-27 17:40 -0400
  Re: Comparison Style Dave Angel <davea@davea.name> - 2013-04-25 23:43 -0400

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