Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.c > #105620

Re: lambda functions in C

From Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups comp.lang.c
Subject Re: lambda functions in C
Date 2017-03-08 23:41 +0000
Organization A noiseless patient Spider
Message-ID <87pohrz687.fsf@bsb.me.uk> (permalink)
References <da2ac707-2a39-41c2-9ac4-20c4811318e8@googlegroups.com> <0ce4976f-49e7-4275-9371-dadbe4388539@googlegroups.com>

Show all headers | View raw

Malcolm McLean <malcolm.mclean5@btinternet.com> writes:

> On Wednesday, March 8, 2017 at 6:04:26 PM UTC, Thiago Adams wrote:
>> One feature I miss from C++ is lambdas expressions.
>> 
>
>> This feature could be added as it is into the C language.
>> The generated code is an internal linkage anonymous function.
>> 
>> This is a kind of feature I would add in my C' extensions.
>> 
>> My question is what would be the syntax for C? Like C++?
>> 
> Baby X makes extensive use of lambdas.

This is likely to be another case of using your own language.  C does
not have lambdas so I doubt you use them a lot.

> The rule is to always pass back a context pointer to the callback.

That's usually implemented as a standard, named function whereas a
lambda is an anonymous function.

A closure is a function value that carries with it some lexical
environment, usually the one it was defined or created in.  A named C
function with a void * parameter is often used in an attempt to model
the behaviour of a closure but it does not come very close as the
argument that gets passed is chosen by the caller and has almost nothing
to do with the names in scope where the function is defined.

It's even further from being a lambda since it lacks the key property of
being anonymous.

Finally, named C functions are not proper values -- they are simply
pointers to static code.  You can't wrap the function pointer and the
extra context parameter up into a new function value such it can be used
in other places, much less used in the construction of further function
vales.

<snip>
-- 
Ben.

Back to comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

lambda functions in C Thiago Adams <thiago.adams@gmail.com> - 2017-03-08 10:04 -0800
  Re: lambda functions in C BartC <bc@freeuk.com> - 2017-03-08 18:20 +0000
    Re: lambda functions in C Chad <cdalten@gmail.com> - 2017-03-08 11:12 -0800
      Re: lambda functions in C Thiago Adams <thiago.adams@gmail.com> - 2017-03-08 11:36 -0800
        Re: lambda functions in C scott@slp53.sl.home (Scott Lurndal) - 2017-03-08 20:43 +0000
        Re: lambda functions in C David Brown <david.brown@hesbynett.no> - 2017-03-08 21:55 +0100
          Re: lambda functions in C Thiago Adams <thiago.adams@gmail.com> - 2017-03-08 13:18 -0800
            Re: lambda functions in C Thiago Adams <thiago.adams@gmail.com> - 2017-03-10 12:44 -0800
        Re: lambda functions in C Chad <cdalten@gmail.com> - 2017-03-08 13:03 -0800
    Re: lambda functions in C Thiago Adams <thiago.adams@gmail.com> - 2017-03-08 11:33 -0800
      Re: lambda functions in C scott@slp53.sl.home (Scott Lurndal) - 2017-03-08 20:46 +0000
        Re: lambda functions in C Thiago Adams <thiago.adams@gmail.com> - 2017-03-08 13:25 -0800
      Re: lambda functions in C "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-03-10 13:55 -0500
        Re: lambda functions in C supercat@casperkitty.com - 2017-03-10 11:09 -0800
          Re: lambda functions in C "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-03-10 14:51 -0500
        Re: lambda functions in C BartC <bc@freeuk.com> - 2017-03-10 19:19 +0000
          Re: lambda functions in C "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-03-10 14:53 -0500
            Re: lambda functions in C BartC <bc@freeuk.com> - 2017-03-11 14:17 +0000
              Re: lambda functions in C "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-03-11 06:55 -0800
                Re: lambda functions in C "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-03-11 07:05 -0800
  Re: lambda functions in C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-08 13:55 -0800
    Re: lambda functions in C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-03-08 23:41 +0000
      Re: lambda functions in C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-09 05:03 -0800
        Re: lambda functions in C Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-03-09 14:06 +0000
        Re: lambda functions in C BartC <bc@freeuk.com> - 2017-03-09 14:20 +0000
          Re: lambda functions in C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-09 08:07 -0800
            Re: lambda functions in C David Brown <david.brown@hesbynett.no> - 2017-03-09 21:50 +0100
              Re: lambda functions in C GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-09 23:38 +0100
                Re: lambda functions in C Ike Naar <ike@iceland.freeshell.org> - 2017-03-09 22:46 +0000
                Re: lambda functions in C GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-10 08:39 +0100
                Re: lambda functions in C Ike Naar <ike@iceland.freeshell.org> - 2017-03-10 08:03 +0000
                Re: lambda functions in C GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-10 09:22 +0100
                Re: lambda functions in C Ike Naar <ike@iceland.freeshell.org> - 2017-03-10 19:24 +0000
                Re: lambda functions in C GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-10 23:23 +0100
                Re: lambda functions in C Ike Naar <ike@iceland.freeshell.org> - 2017-03-11 18:02 +0000
                Re: lambda functions in C Jerry Stuckle <jstucklex@attglobal.net> - 2017-03-09 20:48 -0500
                Re: lambda functions in C GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-10 08:57 +0100
                Re: lambda functions in C Jerry Stuckle <jstucklex@attglobal.net> - 2017-03-10 11:26 -0500
                Re: lambda functions in C GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-10 17:53 +0100
                Re: lambda functions in C Jerry Stuckle <jstucklex@attglobal.net> - 2017-03-10 13:17 -0500
                Re: lambda functions in C David Brown <david.brown@hesbynett.no> - 2017-03-11 17:11 +0100
                Re: lambda functions in C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-10 00:38 -0800
                Re: lambda functions in C GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-10 10:23 +0100
                Re: lambda functions in C Jerry Stuckle <jstucklex@attglobal.net> - 2017-03-10 11:37 -0500
                Re: lambda functions in C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-10 09:07 -0800
                Re: lambda functions in C Jerry Stuckle <jstucklex@attglobal.net> - 2017-03-10 13:22 -0500
                Re: lambda functions in C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-10 10:47 -0800
                Re: lambda functions in C Jerry Stuckle <jstucklex@attglobal.net> - 2017-03-10 14:57 -0500
                Re: lambda functions in C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-10 12:26 -0800
                Re: lambda functions in C Chad <cdalten@gmail.com> - 2017-03-10 12:49 -0800
                Re: lambda functions in C GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-10 23:32 +0100
                Re: lambda functions in C Jerry Stuckle <jstucklex@attglobal.net> - 2017-03-11 12:26 -0500
                Re: lambda functions in C David Brown <david.brown@hesbynett.no> - 2017-03-11 17:17 +0100
                Re: lambda functions in C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-11 10:26 -0800
                Re: lambda functions in C David Brown <david.brown@hesbynett.no> - 2017-03-11 19:48 +0100
                Re: lambda functions in C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-11 12:02 -0800
                Re: lambda functions in C Ian Collins <ian-news@hotmail.com> - 2017-03-12 09:14 +1300
                Re: lambda functions in C "James R. Kuyper" <jameskuyper@verizon.net> - 2017-03-11 15:44 -0500
                Re: lambda functions in C Ian Collins <ian-news@hotmail.com> - 2017-03-12 09:51 +1300
                Re: lambda functions in C "James R. Kuyper" <jameskuyper@verizon.net> - 2017-03-11 16:11 -0500
                Re: lambda functions in C jacobnavia <jacob@jacob.remcomp.fr> - 2017-03-11 22:21 +0100
                Re: lambda functions in C jameskuyper@verizon.net - 2017-03-11 13:36 -0800
                Re: lambda functions in C jacobnavia <jacob@jacob.remcomp.fr> - 2017-03-11 23:48 +0100
                Re: lambda functions in C Ian Collins <ian-news@hotmail.com> - 2017-03-12 11:55 +1300
                Re: lambda functions in C "James R. Kuyper" <jameskuyper@verizon.net> - 2017-03-11 18:34 -0500
                Re: lambda functions in C Ian Collins <ian-news@hotmail.com> - 2017-03-12 15:23 +1300
                Re: lambda functions in C BartC <bc@freeuk.com> - 2017-03-12 11:42 +0000
                Re: lambda functions in C GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-12 13:49 +0100
                Re: lambda functions in C "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-03-12 10:56 -0700
                Re: lambda functions in C jameskuyper@verizon.net - 2017-03-11 15:30 -0800
                Re: lambda functions in C jacobnavia <jacob@jacob.remcomp.fr> - 2017-03-12 00:37 +0100
                Re: lambda functions in C Keith Thompson <kst-u@mib.org> - 2017-03-11 17:23 -0800
                Re: lambda functions in C David Brown <david.brown@hesbynett.no> - 2017-03-12 14:32 +0100
                Re: lambda functions in C Gareth Owen <gwowen@gmail.com> - 2017-03-12 07:22 +0000
                Re: lambda functions in C Ian Collins <ian-news@hotmail.com> - 2017-03-12 11:10 +1300
                Re: lambda functions in C Ian Collins <ian-news@hotmail.com> - 2017-03-12 11:08 +1300
                Re: lambda functions in C GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-12 00:17 +0100
                Re: lambda functions in C David Brown <david.brown@hesbynett.no> - 2017-03-12 14:14 +0100
                Re: lambda functions in C Jerry Stuckle <jstucklex@attglobal.net> - 2017-03-12 09:54 -0400
                Re: lambda functions in C GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-12 15:10 +0100
                Re: lambda functions in C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-12 08:08 -0700
                Re: lambda functions in C GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-12 16:49 +0100
                Re: lambda functions in C Jerry Stuckle <jstucklex@attglobal.net> - 2017-03-12 14:28 -0400
                Re: lambda functions in C GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-13 00:03 +0100
                Re: lambda functions in C Jerry Stuckle <jstucklex@attglobal.net> - 2017-03-12 19:15 -0400
                Re: lambda functions in C David Brown <david.brown@hesbynett.no> - 2017-03-12 18:18 +0100
                Re: lambda functions in C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-12 10:42 -0700
                Re: lambda functions in C David Brown <david.brown@hesbynett.no> - 2017-03-12 20:53 +0100
                Re: lambda functions in C supercat@casperkitty.com - 2017-03-10 07:09 -0800
                Re: lambda functions in C supercat@casperkitty.com - 2017-03-10 08:56 -0800
                Re: lambda functions in C GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-03-10 08:49 +0100
    Re: lambda functions in C Thiago Adams <thiago.adams@gmail.com> - 2017-03-09 04:12 -0800
  Re: lambda functions in C Alain Ketterlin <alain@universite-de-strasbourg.fr.invalid> - 2017-03-09 10:38 +0100
  Re: lambda functions in C Siri Cruise <chine.bleu@yahoo.com> - 2017-03-09 08:48 -0800
    Re: lambda functions in C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-09 09:45 -0800
      Re: lambda functions in C Thiago Adams <thiago.adams@gmail.com> - 2017-03-09 09:51 -0800
    Re: lambda functions in C Thiago Adams <thiago.adams@gmail.com> - 2017-03-09 09:50 -0800
      Re: lambda functions in C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-09 11:08 -0800
        Re: lambda functions in C Ian Collins <ian-news@hotmail.com> - 2017-03-10 08:22 +1300
          Re: lambda functions in C Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-03-09 12:12 -0800
        Re: lambda functions in C Thiago Adams <thiago.adams@gmail.com> - 2017-03-09 11:29 -0800
      Re: lambda functions in C Siri Cruise <chine.bleu@yahoo.com> - 2017-03-09 13:33 -0800
        Re: lambda functions in C Thiago Adams <thiago.adams@gmail.com> - 2017-03-09 13:42 -0800
          Re: lambda functions in C Ian Collins <ian-news@hotmail.com> - 2017-03-10 11:02 +1300
          Re: lambda functions in C Thiago Adams <thiago.adams@gmail.com> - 2017-03-09 14:30 -0800
          Re: lambda functions in C Siri Cruise <chine.bleu@yahoo.com> - 2017-03-09 15:07 -0800
  Re: lambda functions in C jacobnavia <jacob@jacob.remcomp.fr> - 2017-03-11 21:45 +0100
    Re: lambda functions in C Thiago Adams <thiago.adams@gmail.com> - 2017-03-13 06:13 -0700

csiph-web