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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: [ On topic, amazingtly ]: labels and declarations
Date: Fri, 22 Mar 2019 11:13:56 -0700
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Manfred <noname@add.invalid> writes:
> On 3/22/2019 4:22 AM, Robert Wessel wrote:
>>> This problem apparently follows from labels being neither statements nor
>>> declarations, but instead entities of their own slapped into the
>>> language to pair their ASM counterparts.
>>> Today one may say they were not thought well enough in the beginning,
>>> but considering the status of CS in the '70s it would have been probably
>>> hard to foresee this kind of implications at the time, and hey, they
>>> served the purpose so far.
>> 
>> Labels are an optional prefix to a statement.
>
> i.e. a direct import from ASM, without further attempt for integration 
> with the language structure.

Not really.  The syntax and semantics of C's labels are similar to those
of assembly language labels, but I'm not sure how else you'd define
them.  There's not much you could do to integrate them more closely into
the rest of the language.  Their syntax is defined using the same BNF as
everything else:

    labeled-statement:
        identifier : statement
        case constant-expression : statement
        default : statement

Compare that to the preprocessor, which really isn't tightly integrated
into the language structure.

-- 
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 */