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From: Thiago Adams <thiago.adams@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: on allowing "int a" definition everywhere
Date: Thu, 22 Aug 2024 08:10:34 -0300
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On 22/08/2024 07:00, Bart wrote:
> I assume the (...) tests the value of 'f'? If so then perhaps this is a 
> shorter way of expressing the same thing:
> 
>      {
>          FILE * f = fopen("file.txt", "r");
>          if (f) {
>              /* … */
>              fclose(f);
>          }
>      }
>      fwrite(f, …);

Yes, this is the equivalent code.

C++ allows two forms. One with explicit check and another one with 
implicit check.


  if (FILE* f = fopen("file.txt", "r"); f) /*f is checked explicitly*/
  {
      /*...*/
      fclose(f);
  }

  if (FILE* f = fopen("file.txt", "r"))  /*f is checked implicitly*/
  {
      /*...*/
      fclose(f);
  }

I also have considered for cake to have a extra part that is "defer" part.

if (FILE* f = fopen("file.txt", "r"); f; fclose(f))
{
}

But if 'defer' were added to C2Y, we could then do the following:

if (FILE* f = fopen("file.txt", "r"); f; )
{
   defer fclose(f);
   /*...*/
}


Sometimes, too much syntactic sugar is not good because it creates too 
many variants.