[Gs-devel] A small proposal about improving GS coding style : CheckRET

[Igor V. Melichev]

This is very small proposal about improving GS coding style.

I'm tired of fragments like this :

    int code = function(arguments);
    if (code < 0)
        return code;

They make code cumbersome and it cannot fit into display.
My old experience is to define macro :

#define CheckRET(a) { int temporaryvariable = (a); if (temporaryvariable <
0) return temporaryvariable; }

such that the code looks like this :

    CheckRET(function(arguments));

I think that we don't need other predicates than '<0'.
If you think different, please explain.

I don't know, in which header file to insert this macro.
It must be globally accessible. Probably old GS developers can
choose a good place for it.

Yes, this thing is not perfect :

1. Sometimes other predicates wanted.

2. Incorrect code :

   double temporaryvariable = 0;
   CheckRET(function(&temporaryvariable));

3. Syntax error :

   if (x)
     CheckRET(function(arguments)); /* ' }; else' isn't valid syntax */
   else
     something();


4. Syntax error :

   void f()
   { CheckRET(function(arguments)); /* Can't return value from void function
*/
   }

But I use this thing during 4 years and I was very happy before I
entered GS. Now I'm unhappy because GS doesn't have it.
Lets define. Just try and you'll find it useful.

Of cause, one can propose multiple similar macros for problems 1-4.
But I believe that the power of my solution is to keep a single macro.
This is a discipline of mind (a kind of "structural" programming).

I don't propose to replace old code with this.
But I'd like to use it in new code.
But I don't like to define it locally multiple times.

Igor.




===== Igor V. Melichev, St.Petersburg, Russia.        =====
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