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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: [ On topic, amazingtly ]: labels and declarations
Date: Sun, 17 Mar 2019 16:16:01 -0700
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Richard Damon <Richard@Damon-Family.org> writes:
[...]
> This unfortunately leads to the following being grammatically correct:
>
> if(flag) int x;
>
> which would mean that the following code might be valid or not depending
> of if flag was true at run time, or
>
> if(flag) int x;
> else     float x;
>
> where the type of x changes at run time, or even
[...]

C++ allows this; a declaration (if it appears inside a function
defintion) is a kind of statement.  The scope of x is limited to the
declaration-statement, so the above is equivalent to:

    if (flag) { int x; }
    else      { float x; }

which is valid in C.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Will write code for food.
void Void(void) { Void(); } /* The recursive call of the void */