Re: which of these 3 casts would you prefer?

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From	"Duga Chernobyl" <duga_c3@gmx.com>
Newsgroups	comp.lang.c++
Subject	Re: which of these 3 casts would you prefer?
Date	Fri, 26 Aug 2011 10:05:51 +0200
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Dnia 25-08-2011 o 23:58:56 A <a@a.a> napisał(a):

> int Callback(void *pThis)
> {
> TMyClass *pMC = (TMyClass*)pThis;                    // C style
>
> TMyClass *pMC = static_cast<TMyClass*>(pThis);       // C++ style but the
>                                                      // same as above
>
> TMyClass *pMC = reinterpret_cast<TMyClass*>(pThis);  // Doesn't check if
>                                                      // input type was
>                                                      // pointer, possibly
>                                                      // dangerous
> }
>
> these 3 do essentially the same. is there any preferred one for void*  
> cast
> like this and why? any difference in speed?
>
>
>
>

IMHO there is no place for preferences.

The first is used in c and should be used only in C.
The second is from C++ and should be used mostly (compiler check if  
conversion is usable)
The third is a equivalent of the c solution. Compiler checks nothing.

In c++ should be used only c++ conversion, because mostly compiler (not in  
reinterpret conv.) does some checks of common sense of this conversion.
And c++ conversion are long and easy to find. The creator of c++ some gave  
arguments: the place of most errors is conversion ;-)

dynamic_cast is used for child class pointers conversion.

Thread

which of these 3 casts would you prefer? "A" <a@a.a> - 2011-08-25 23:58 +0200
  Re: which of these 3 casts would you prefer? Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-25 16:19 -0700
  Re: which of these 3 casts would you prefer? Robert Wessel <robertwessel2@yahoo.com> - 2011-08-25 18:59 -0500
  Re: which of these 3 casts would you prefer? "Alf P. Steinbach" <alf.p.steinbach:usenet@gmail.com> - 2011-08-26 08:02 +0200
  Re: which of these 3 casts would you prefer? "Duga Chernobyl" <duga_c3@gmx.com> - 2011-08-26 10:05 +0200
    Re: which of these 3 casts would you prefer? "A" <a@a.a> - 2011-08-26 14:40 +0200
      Re: which of these 3 casts would you prefer? Leigh Johnston <leigh@i42.co.uk> - 2011-08-26 13:59 +0100
      Re: which of these 3 casts would you prefer? "Duga Chernobyl" <duga_c3@gmx.com> - 2011-08-26 15:19 +0200
        Re: which of these 3 casts would you prefer? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-08-26 21:27 +0000
          Re: which of these 3 casts would you prefer? "Alf P. Steinbach" <alf.p.steinbach:usenet@gmail.com> - 2011-08-27 01:28 +0200
          Re: which of these 3 casts would you prefer? "Duga Chernobyl" <duga_c3@gmx.com> - 2011-08-27 10:23 +0200
            Re: which of these 3 casts would you prefer? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-08-27 12:10 +0000
          Re: which of these 3 casts would you prefer? RaZiel <raziel_206_@hotmail.com> - 2011-08-27 21:55 +0200
          Re: which of these 3 casts would you prefer? Miles Bader <miles@gnu.org> - 2011-09-01 08:03 +0900
            Re: which of these 3 casts would you prefer? BGB <cr88192@hotmail.com> - 2011-08-31 23:11 -0700
            Re: which of these 3 casts would you prefer? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-09-01 19:34 +0000
              Re: which of these 3 casts would you prefer? Joshua Maurice <joshuamaurice@gmail.com> - 2011-09-01 15:37 -0700
                Re: which of these 3 casts would you prefer? gwowen <gwowen@gmail.com> - 2011-09-02 00:30 -0700
                Re: which of these 3 casts would you prefer? Miles Bader <miles@gnu.org> - 2011-09-03 18:26 +0900
      Re: which of these 3 casts would you prefer? Edek <edek.pienkowski@gmail.com> - 2011-08-26 15:29 +0200
      Re: which of these 3 casts would you prefer? BGB <cr88192@hotmail.com> - 2011-08-27 09:35 -0700
        Re: which of these 3 casts would you prefer? Juha Nieminen <nospam@thanks.invalid> - 2011-08-27 18:38 +0000
          Re: which of these 3 casts would you prefer? Noah Roberts <roberts.noah@gmail.com> - 2011-08-27 12:32 -0700
            Re: which of these 3 casts would you prefer? BGB <cr88192@hotmail.com> - 2011-08-27 14:51 -0700
              Re: which of these 3 casts would you prefer? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-08-29 14:10 +0000
                Re: which of these 3 casts would you prefer? BGB <cr88192@hotmail.com> - 2011-08-30 07:23 -0700
            Re: which of these 3 casts would you prefer? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-08-29 11:32 +0000
          Re: which of these 3 casts would you prefer? BGB <cr88192@hotmail.com> - 2011-08-27 14:37 -0700
            Re: which of these 3 casts would you prefer? Ian Collins <ian-news@hotmail.com> - 2011-08-28 10:06 +1200
              Re: which of these 3 casts would you prefer? BGB <cr88192@hotmail.com> - 2011-08-27 15:27 -0700
                Re: which of these 3 casts would you prefer? Ian Collins <ian-news@hotmail.com> - 2011-08-28 10:47 +1200
                Re: which of these 3 casts would you prefer? Noah Roberts <roberts.noah@gmail.com> - 2011-08-27 15:42 -0700
                Re: which of these 3 casts would you prefer? Nobody <nobody@nowhere.com> - 2011-08-28 04:15 +0100
            Re: which of these 3 casts would you prefer? Noah Roberts <roberts.noah@gmail.com> - 2011-08-27 15:52 -0700
              Re: which of these 3 casts would you prefer? BGB <cr88192@hotmail.com> - 2011-08-28 01:54 -0700
                Re: which of these 3 casts would you prefer? Keith H Duggar <duggar@alum.mit.edu> - 2011-09-04 19:16 -0700
            Re: which of these 3 casts would you prefer? Juha Nieminen <nospam@thanks.invalid> - 2011-08-29 18:16 +0000
              Re: which of these 3 casts would you prefer? Noah Roberts <roberts.noah@gmail.com> - 2011-08-29 16:35 -0700
                Re: which of these 3 casts would you prefer? Nobody <nobody@nowhere.com> - 2011-08-30 04:13 +0100
                Re: which of these 3 casts would you prefer? Juha Nieminen <nospam@thanks.invalid> - 2011-08-30 06:03 +0000
              Re: which of these 3 casts would you prefer? BGB <cr88192@hotmail.com> - 2011-08-30 07:12 -0700
                Re: which of these 3 casts would you prefer? Juha Nieminen <nospam@thanks.invalid> - 2011-08-31 06:16 +0000
                Re: which of these 3 casts would you prefer? BGB <cr88192@hotmail.com> - 2011-09-01 03:05 -0700
                Re: which of these 3 casts would you prefer? Juha Nieminen <nospam@thanks.invalid> - 2011-09-01 07:00 +0000
                Re: which of these 3 casts would you prefer? BGB <cr88192@hotmail.com> - 2011-08-31 13:21 -0700
          Re: which of these 3 casts would you prefer? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-08-28 19:30 +0000
      Re: which of these 3 casts would you prefer? Noah Roberts <roberts.noah@gmail.com> - 2011-08-27 12:19 -0700
        Re: which of these 3 casts would you prefer? Dombo <dombo@disposable.invalid> - 2011-08-28 12:08 +0200
        Re: which of these 3 casts would you prefer? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-08-28 19:44 +0000
          Re: which of these 3 casts would you prefer? Noah Roberts <roberts.noah@gmail.com> - 2011-08-28 13:41 -0700
    Re: which of these 3 casts would you prefer? Anand Hariharan <mailto.anand.hariharan@gmail.com> - 2011-08-26 07:30 -0700

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