From 8034516631729664096 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: f78e5,a69618ea97f65037 X-Google-Attributes: gidf78e5,public From: "Paul D. DeRocco" Subject: Re: nested functions Date: 1998/04/29 Message-ID: <3546C3C8.898F123F@ix.netcom.com>#1/1 X-Deja-AN: 348660901 Approved: Fergus Henderson Content-Transfer-Encoding: 7bit References: <6hac23$8lb$1@news2.isdnet.net> <353A6B2D.C2904893@concentric.net> <353F43D1.2781E494@ips.cs.tu-bs.de> <3545EA31.DE87C4E6@concentric.net> X-Original-Date: Wed, 29 Apr 1998 02:08:08 -0400 Content-Type: text/plain; charset=us-ascii Organization: Vast Right-Wing Conspiracy X-NETCOM-Date: Tue Apr 28 11:09:50 PM PDT 1998 X-Auth: PGPMoose V1.1 PGP comp.std.c++ iQBFAgUANUbN/uEDnX0m9pzZAQEiaQF/R0MA/ZcAgyhLPr7IONa3FeAwSI72jRv8 O0XjUJGKyNnyfwlRGs6EjopOy6tQtNoT =SsVe Mime-Version: 1.0 Newsgroups: comp.std.c++ Bradd W. Szonye wrote: > > Okay, no argument there. I thought the original poster was talking > about > the 'toy' local functions in, say, Pascal, not the higher-order > functions available in functional programming languages, which I'll > agree are very powerful. What I bemoan the lack of is precisely what you call "toy" local functions. I know I can do fancier stuff with functors that carry data along with them. However, every now and then, I have to write some big function, perhaps containing a long switch statement, and I find there's the same little tidbit of code in it over and over and over again, that I'd really like to wrap in a function, except that it needs access to two or three of the local variables of the outer function. For instance, suppose I'm writing a disassembler that fetches bytes from memory, and appends characters to a character buffer: int disassemble( const unsigned char* bin, // instruction char* buf, // result buffer unsigned buflen); // buffer length Such code generally involves big switch statements, but I need to produce output by appending to the buffer and checking against the buffer length. This is done in dozens of places, so I'd like to do it with a function: void append(char c, char*& buf, unsigned& buflen) { *buf++ = c; if (!--buflen) throw length_error(); } If I could write it as a nested function, I could leave off the buf and buflen parameters, which makes the resulting code more efficient in terms of space, speed, and clarity. Since I can't do that, I end up storing buf and buflen into globals, which is a kludge. -- Ciao, Paul --- [ 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 ]