From 5028271321564392920 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: f78e5,9d57bb38940f08c2 X-Google-Attributes: gidf78e5,public From: Francis Glassborow Subject: Re: References to functions allowed? Date: 1999/01/19 Message-ID: #1/1 X-Deja-AN: 434448181 Approved: stephen.clamage@sun.com (comp.std.c++) References: <36A222B3.E51DFD28@ibm.net> <780f6f$kjs$1@engnews2.Eng.Sun.COM> X-UID: 0000000001 X-Status: $$$T Organization: Southfield Microcomputer SS Mime-Version: 1.0 Reply-To: Francis Glassborow Newsgroups: comp.std.c++ Originator: clamage@taumet In article <780f6f$kjs$1@engnews2.Eng.Sun.COM>, Steve Clamage writes > >Gabriel Dos_Reis writes: > >>Francis Glassborow writes: > >>[...] > >>> >>> In simple terms IMO I do not think there is any syntactic way that you >>> can write a reference to a function (*f does not work because under the >>> rules that is converted to a pointer) > >>Was that intended or just an oversight ? > >I think it was an oversight on Francis' part. :-) > >Sections 3.9.2 and 8.3.2 mention references to functions, and >section 8.5.3 gives this example of a reference to function: > > int (&rg)(int) = g; // rg refers to the function g Well I stand corrected, but this seems to buy us nothing while meaning that the strict rules for function names in C and C++ are different. A function name is always a pointer type in C which the function 'operator' dereferences. Now presumably we have to provide a conversion rule for g (actually see 4.3) in the above (or to convert it to a function pointer elsewhere). And CodeWarrior compiles such code. However what use is it? Suppose that we try it in a template: template void garbage(T t); How are we to use this if T is a function type? I cannot see how: template class rubbish { } is any more useful. Can anyone suggest anyway in which this facility provides any functionality? Now how do I dereference a function pointer to bind it to a reference? Is this well formed? int fn (int); int (*fnptr)(int) = fn; int (&fnref)(int) = static_cast fnptr; Francis Glassborow Chair of Association of C & C++ Users 64 Southfield Rd Oxford OX4 1PA +44(0)1865 246490 All opinions are mine and do not represent those of any organisation [ 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 ]