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From: Ben Bacarisse <ben@bsb.me.uk>
Newsgroups: comp.lang.c
Subject: Re: on allowing "int a" definition everywhere
Date: Thu, 22 Aug 2024 11:29:45 +0100
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Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:

> The original code:
>
>     if (FILE* f = fopen("file.txt", "r"))

I think the proposal would be a declaration to precede an expression:

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

>     {
>        /*...*/ fclose(f);
>     }
>
> doesn't allow for taking some non-trivial action of the fopen() call
> fails, but if a declaration in an if condition is visible in the else
> clause, you could write something like:
>
>     if (FILE* f = fopen("file.txt", "r")) {
>        /*...*/
>        fclose(f);
>     }
>     else {
>         perror("file.txt");
>         exit(EXIT_FAILURE); // or try something else
>     }

What's the significance of the declared name being in scope in the else
clause here?

-- 
Ben.