From -8029389521258309194 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: f78e5,fb1a92fa405c930c X-Google-Attributes: gidf78e5,public From: James.Kanze@dresdner-bank.com Subject: Re: nested functions Date: 1999/06/23 Message-ID: <7k60qd$rgj$1@nnrp1.deja.com>#1/1 X-Deja-AN: 492912513 Approved: Valentin Bonnard References: <7jd4c5$nup$1@nnrp1.deja.com> <7jjjr6$r02$1@nnrp1.deja.com> <7jma5c$i85@abyss.West.Sun.COM> <37fc8bd2.644752685@nntp.ix.netcom.com> X-Original-Date: Tue, 15 Jun 1999 17:00:05 GMT X-Http-User-Agent: Mozilla/4.6 [en] (WinNT; I) X-Http-Proxy: 1.0 x32.deja.com:80 (Squid/1.1.22) for client 193.194.7.71 Organization: Deja.com - Share what you know. Learn what you don't. X-Article-Creation-Date: Tue Jun 15 17:00:05 1999 GMT X-Auth: PGPMoose V1.1 PGP comp.std.c++ iQBVAwUAN3DNq6wEuYhIxRhxAQGBAQH/ZCT1wW0CyXwBNgbVZs4JmtQZ/XdcsdNG l0R2nxWNtHMtdTa0d4sH8kZcg1nUobHoNfRDlRE3c8arH9yZ5DoH4A== =BC2h Newsgroups: comp.std.c++ In article <37fc8bd2.644752685@nntp.ix.netcom.com>, source@netcom.com (David Harmon) wrote: > > On 10 Jun 99 16:20:58 GMT in comp.std.c++, ark@research.att.com > (Andrew Koenig) wrote: > > >> Why do local functions have to have the same calling sequence as non-local > >> functions? > > > >Because otherwise, you can't define a variable > >(of type pointer to function) that can potentially > >contain the address of a local function or a non-local > >function. > > Just like you can't define a variable that can hold both a pointer > to a member function or a pointer to a non-member function. A local > function is actually more like a member function than a non-member > function, but instead of 'this' it gets a pointer to an implicit > local context object (AKA display.) In that case, why not just make it a pointer to member of a class deriving from __local_scope. The difference, in both cases, is that the function to which it is passed as a parameter must know that it is dealing with a local function/a pointer to member function, and handle it separately. For a pointer to member function, this is a requirement anyway, because the pointer to member function is *not* bound to an instance of the class. The caller must provide the instance. A pointer to a local function, on the other hand, is bound, and can be used exactly like a pointer to any other function. -- James Kanze mailto: James.Kanze@dresdner-bank.com Conseils en informatique orientie objet/ Beratung in objekt orientierter Datenverarbeitung Ziegelh|ttenweg 17a, 60598 Frankfurt, Germany Tel. +49 (069) 63 19 86 27 Sent via Deja.com http://www.deja.com/ Share what you know. Learn what you don't. --- [ comp.std.c++ is moderated. To submit articles, try just posting with ] [ your news-reader. If that fails, use mailto:std-c++@ncar.ucar.edu ] [ --- Please see the FAQ before posting. --- ] [ FAQ: http://reality.sgi.com/austern_mti/std-c++/faq.html ]