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Re: Function factories

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Le 23/08/12 18:29, Anand Hariharan a écrit :
> On Aug 23, 10:13 am, James Kuyper <jameskuy...@verizon.net> wrote:
>> On 08/23/2012 08:27 AM, Chicken McNuggets wrote:
>>
>>> On 22/08/2012 16:05, James Kuyper wrote:
>>
>>>> However, I think that compile() looks horribly type-unsafe.
>>
>>> Type safety in C? That's a novel concept :).
>>
>> Is it? Try compiling the following code:
>>
>> int main(void)
>> {
>>          double d;
>>          int *pi = &d;
>>          return 0;
>> }
>
> One additional line (that doesn't involve any casts) is sufficient -
>
> int main(void)
> {
>      double d;
>      void *pv = &d;
>      int *pi = pv;
>      return 0;
> }
>
> $ gcc -W -Wall -ansi -pedantic foo.c
> foo.c: In function ‘main’:
> foo.c:6:10: warning: unused variable ‘pi’
>
>

C allows you to interpret ANY part of memory as something else if you 
(as you have shown) are careful to avoid the built-in barriers of the 
language.

Interpreting doubles as integers is very useful if you want to test
some bits or manipulate some bits of the binary representation without
going through expensive floating point operations. The whole Sun math 
library is built using this kind of code, and you can do that in C since 
it is a language that doesn't IMPOSE anything to the programmer, like 
C#, C++ or Cwhatever.

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Function factories Edward Rutherford <edward.p.rutherford79@REMOVETHIS.gmail.com> - 2012-08-21 20:36 +0000
  Re: Function factories Nobody <nobody@nowhere.com> - 2012-08-21 21:55 +0100
    Re: Function factories Edward Rutherford <edward.p.rutherford79@REMOVETHIS.gmail.com> - 2012-08-22 16:36 +0000
      Re: Function factories James Kuyper <jameskuyper@verizon.net> - 2012-08-22 13:01 -0400
        Re: Function factories Edward Rutherford <edward.p.rutherford79@REMOVETHIS.gmail.com> - 2012-08-22 18:33 +0000
        Re: Function factories James Kuyper <jameskuyper@verizon.net> - 2012-08-22 22:26 -0400
  Re: Function factories David Brown <david@westcontrol.removethisbit.com> - 2012-08-22 08:34 +0200
    Re: Function factories Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-08-22 01:52 -0700
      Re: Function factories David Brown <david@westcontrol.removethisbit.com> - 2012-08-22 11:34 +0200
      Re: Function factories Gareth Owen <gwowen@gmail.com> - 2012-08-24 17:30 +0100
    Re: Function factories Gareth Owen <gwowen@gmail.com> - 2012-08-24 17:29 +0100
  Re: Function factories jacob navia <jacob@spamsink.net> - 2012-08-22 12:32 +0200
    Re: Function factories tom st denis <tom@iahu.ca> - 2012-08-22 07:40 -0700
      Re: Function factories James Kuyper <jameskuyper@verizon.net> - 2012-08-22 11:05 -0400
        Re: Function factories jacob navia <jacob@spamsink.net> - 2012-08-23 11:08 +0200
        Re: Function factories Chicken McNuggets <chicken@mcnuggets.com> - 2012-08-23 13:27 +0100
          Re: Function factories James Kuyper <jameskuyper@verizon.net> - 2012-08-23 11:13 -0400
            Re: Function factories "Heinrich Wolf" <invalid@invalid.invalid> - 2012-08-23 18:18 +0200
              Re: Function factories James Kuyper <jameskuyper@verizon.net> - 2012-08-23 12:40 -0400
            Re: Function factories Anand Hariharan <mailto.anand.hariharan@gmail.com> - 2012-08-23 09:29 -0700
              Re: Function factories jacob navia <jacob@spamsink.net> - 2012-08-23 18:44 +0200
              Re: Function factories James Kuyper <jameskuyper@verizon.net> - 2012-08-23 12:46 -0400
            Re: Function factories Chicken McNuggets <chicken@mcnuggets.com> - 2012-08-23 18:02 +0100
              Re: Function factories jacob navia <jacob@spamsink.net> - 2012-08-23 19:24 +0200
                Re: Function factories eq mail <eq.mail.id@gmail.com> - 2012-08-23 18:07 -0700
                Re: Function factories Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-23 21:30 -0400
                Re: Function factories eq mail <eq.mail.id@gmail.com> - 2012-08-23 21:46 -0700
              Re: Function factories James Kuyper <jameskuyper@verizon.net> - 2012-08-23 13:35 -0400
                Re: Function factories jacob navia <jacob@spamsink.net> - 2012-08-23 20:13 +0200
              Re: Function factories eq mail <eq.mail.id@gmail.com> - 2012-08-23 17:57 -0700
              Re: Function factories Andrew Cooper <amc96@cam.ac.uk> - 2012-08-25 02:35 +0100
            Re: Function factories Melzzzzz <mel@zzzzz.invalid> - 2012-08-23 21:21 +0200
              Re: Function factories James Kuyper <jameskuyper@verizon.net> - 2012-08-23 15:36 -0400
                Re: Function factories Melzzzzz <mel@zzzzz.invalid> - 2012-08-23 22:09 +0200
                Re: Function factories James Kuyper <jameskuyper@verizon.net> - 2012-08-23 16:20 -0400
                Re: Function factories Melzzzzz <mel@zzzzz.com> - 2012-08-23 22:33 +0200
                Re: Function factories James Kuyper <jameskuyper@verizon.net> - 2012-08-23 17:07 -0400
                Re: Function factories Keith Thompson <kst-u@mib.org> - 2012-08-23 14:51 -0700
                Re: Function factories Melzzzzz <mel@zzzzz.com> - 2012-08-24 00:09 +0200
                Re: Function factories James Kuyper <jameskuyper@verizon.net> - 2012-08-23 19:01 -0400
                Re: Function factories Keith Thompson <kst-u@mib.org> - 2012-08-23 16:31 -0700
                Re: Function factories Melzzzzz <mel@zzzzz.com> - 2012-08-24 18:31 +0200
                Re: Function factories Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-08-24 02:37 -0700

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