From 3867667611266131186 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 109fba,ac06fef48c3c04df X-Google-Attributes: gid109fba,public X-Google-Thread: f78e5,ac06fef48c3c04df X-Google-Attributes: gidf78e5,public X-Google-ArrivalTime: 1995-01-27 18:01:50 PST Newsgroups: comp.lang.c++,comp.std.c++ Path: nntp.gmd.de!newsserver.jvnc.net!howland.reston.ans.net!pipex!uunet!news.cygnus.com!news!jason From: jason@cygnus.com (Jason Merrill) Subject: Re: friends and local classes In-Reply-To: andrewfg@dai.ed.ac.uk's message of Fri, 27 Jan 1995 10:26:33 GMT Content-Type: text/plain; charset=US-ASCII Message-ID: Followup-To: comp.lang.c++,comp.std.c++ Sender: news@cygnus.com Nntp-Posting-Host: phydeaux.cygnus.com Organization: Cygnus Support, Mountain View, CA References: <3g5qc6$16p@news.cc.utah.edu> <3g5rei$dl8@news.panix.com> Mime-Version: 1.0 Date: Sat, 28 Jan 1995 02:01:50 GMT Lines: 35 Xref: nntp.gmd.de comp.lang.c++:88263 comp.std.c++:11267 >>>>> Andrew Fitzgibbon writes: > swillden@fcom.cc.utah.edu (Shawn Willden) wrote: >> >> Sam Fenster (fenster@ground.cs.columbia.edu) wrote: >> : Ideally, we'd have local functions too, for similar reasons (e.g. a comparison >> : function to pass to "qsort"). I don't expect that soon. But let's not get >> : rid of local classes, OK? >> >> Just make a local class with a static function if you need a local function. >> [paraphrasing:] >> void functionWithLocalFunction() { >> struct Local { >> int static compare(const void* a, const void* b) >> {...} >> }; >> qsort(array, sizeof(array)/sizeof(array[0]), sizeof(array), >> &Local::compare); > That's not a local function. It doesn't have lexically scoped access to > the surrounding function's variables. It is as hard to implement this > properly as it is to implement proper local functions. Actually, it does have lexically scoped access to the surrounding function's variables. It's just that using an auto variable or a parameter is ill-formed. > I expect that just after GNU pascal comes out G++ will support local > functions ... Jason? :) Well, GNU C already supports nested functions, so it doesn't need to wait for GNU pascal. It just needs to wait for someone to implement it (which may be happening). Jason