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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: >< swap operator
Date: Mon, 08 Oct 2018 10:49:26 -0700
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Keith Thompson <kst-u@mib.org> writes:
[...]
> There's a possible misunderstanding that occurred to me after I wrote
> the above.  The semicolon is unambiguously *part of* the syntax of the
> statement.  For example, this:
>
>     return 42;
>
> isn't a return statement followed by a semicolon.  It's a return
> statement consisting of three tokens: `return`, `42`, and `;`.  And
> there's no explicit general rule about statements being terminated
> by semicolons; the grammar production for each kind of statement
> (except for the compound-statement) includes the semicolon token.

Let me amend my previous, um, statement.

There are several kinds of statements whose syntax does not include
a trailing semicolon.  The ones that do are:

    expression-statement (which includes the null statement)
    do/while
    goto
    continue
    break
    return

An if statement, for example, might end in a semicolon if the
substatement does.

Anyone who thinks semicolons are unimportant should consider
    if (condition) do_something();
vs.
    if (condition); do_something();

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"