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Re: own initialization before calling parent's constructor

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avasilev wrote:
> Hello,
> The subject says it - is it legal to initialize fields of the derived
> before calling the parent's consctructor, in the initialization list.
> For example:
> 
> class Base
> {
> public:
>    int b;
>    B(int arg):b(arg){};
> };
> 
> class Derived: public Base
> {
>   int d;
>   int calculateValue() {return d+5};
>   Derived(int arg):
>     d(arg), B(calculateValue()){};
> };
> 
> Greetings
> Alex

See the boost base from member idiom at:

http://www.boost.org/doc/libs/1_48_0/libs/utility/base_from_member.html

Jeff

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own initialization before calling parent's constructor avasilev <alxvasilev@gmail.com> - 2011-12-08 05:07 -0800
  Re: own initialization before calling parent's constructor Victor Bazarov <v.bazarov@comcast.invalid> - 2011-12-08 09:03 -0500
    Re: own initialization before calling parent's constructor avasilev <alxvasilev@gmail.com> - 2011-12-08 08:12 -0800
      Re: own initialization before calling parent's constructor Victor Bazarov <v.bazarov@comcast.invalid> - 2011-12-08 12:04 -0500
  Re: own initialization before calling parent's constructor Bart v Ingen Schenau <bart@ingen.ddns.info> - 2011-12-08 16:09 +0100
    Re: own initialization before calling parent's constructor avasilev <alxvasilev@gmail.com> - 2011-12-08 08:10 -0800
      Re: own initialization before calling parent's constructor Victor Bazarov <v.bazarov@comcast.invalid> - 2011-12-08 12:05 -0500
        Re: own initialization before calling parent's constructor avasilev <alxvasilev@gmail.com> - 2011-12-08 10:22 -0800
          Re: own initialization before calling parent's constructor Victor Bazarov <v.bazarov@comcast.invalid> - 2011-12-08 13:44 -0500
          Re: own initialization before calling parent's constructor Gert-Jan de Vos <gert-jan.de.vos@onsneteindhoven.nl> - 2011-12-08 10:51 -0800
            Re: own initialization before calling parent's constructor Victor Bazarov <v.bazarov@comcast.invalid> - 2011-12-08 14:04 -0500
            Re: own initialization before calling parent's constructor avasilev <alxvasilev@gmail.com> - 2011-12-08 11:07 -0800
            Re: own initialization before calling parent's constructor Stuart Redmann <DerTopper@web.de> - 2011-12-09 05:43 -0800
          Re: own initialization before calling parent's constructor Goran <goran.pusic@gmail.com> - 2011-12-08 11:09 -0800
            Re: own initialization before calling parent's constructor avasilev <alxvasilev@gmail.com> - 2011-12-08 11:34 -0800
              Re: own initialization before calling parent's constructor Victor Bazarov <v.bazarov@comcast.invalid> - 2011-12-08 15:15 -0500
              Re: own initialization before calling parent's constructor Goran <goran.pusic@gmail.com> - 2011-12-09 00:07 -0800
                Re: own initialization before calling parent's constructor avasilev <alxvasilev@gmail.com> - 2011-12-09 05:54 -0800
      Re: own initialization before calling parent's constructor Kevin McCarty <kmccarty@gmail.com> - 2011-12-08 09:27 -0800
        Re: own initialization before calling parent's constructor avasilev <alxvasilev@gmail.com> - 2011-12-08 10:40 -0800
          Re: own initialization before calling parent's constructor Victor Bazarov <v.bazarov@comcast.invalid> - 2011-12-08 13:55 -0500
          Re: own initialization before calling parent's constructor Kevin McCarty <kmccarty@gmail.com> - 2011-12-08 12:41 -0800
      Re: own initialization before calling parent's constructor jgk@panix.com (Joe keane) - 2011-12-08 21:20 +0000
  Re: own initialization before calling parent's constructor Paavo Helde <myfirstname@osa.pri.ee> - 2011-12-08 11:17 -0600
  Re: own initialization before calling parent's constructor Jeff Flinn <TriumphSprint2000@hotmail.com> - 2011-12-08 16:42 -0500

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