Re: [C] return statement in void function?

From: Anthony Borla (ajborla_at_bigpond.com)
Date: 01/12/04

  • Next message: Lyn Powell: "Re: [C] return statement in void function?" 
    Date: Mon, 12 Jan 2004 13:15:28 GMT

    "Arthur J. O'Dwyer" <ajo@nospam.andrew.cmu.edu> wrote in message
    news:Pine.LNX.4.58-036.0401120104290.19968@unix46.andrew.cmu.edu...
    >
    > On Mon, 12 Jan 2004, Anthony Borla wrote:
    > >
    > > You may be interested to know that you can do this
    > [in C++, that is]:
    > >
    > > void f() { return void(); }
    > >
    > > as is this:
    > >
    > > void g() {}
    > > void h() { return g(); }
    > >
    > > Yes, it may seem strange, but it is allowed [I suspect] to
    > > maintain syntactic consistency.
    >
    > However, both of these tricks are not allowed in C.
    >

    I only noticed the [C] identifier in the Subject field a few hours *after* I
    posted - how's that for being blinkered :) ?

    I suppose one benefit of my post, though, was to provide the OP with *more*
    information than was required [got to put a positive spin on it somehow ;)
    !].

    >
    > C++, as far as I know, allows them; but the first is
    > a syntax error in C and the second one, despite maybe
    > being "consistent," doesn't have any advantage
    > over
    >
    > void h() { g(); return; }
    >
    > which is probably why C doesn't bother to allow it.
    >

    This:

         void f() { return void(); }

    is not legal C because the language doesn't support temporary objects [let
    alone permanent ones ;)].

    I suspect the following:

        void g() {}
        void h() { return g(); }

    is also allowed in C++ as a consequence of temporary object support since:

        return g();

    is probably optimised to:

        return void();

    Thus, this is illegal in C for the same reason ?

    Cheers,

    Anthony Borla

  • Next message: Lyn Powell: "Re: [C] return statement in void function?"