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Re: Deriving from concrete types like std::list

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Urs Thuermann wrote:
>
>        class StmtList : public Stmt, public std::list <Stmt *> {
>        public:
>                virtual void exec() {
>                        const_iterator it;
>                        for (it = begin(); it != end(); ++it)
>                                (*it)->exec();
>                }
>        };
>
>        // in the parser
>                stmt_list->push_back(stmt);
>
> Is this, according to Stroustrup, the wrong approach?  Instead of
> deriving I could have a member of type list <Stmt *> in class
> StmtList but iterating would look more cumbersome and I had to
> implement my own push_back() that calls push_back() for that list
> member, etc.  After all, a statement list *is* a list.  Shouldn't I
> express this relationship by derivation?
>

Having the list as a member seems a much better idea.

How hard is it to write l.begin() instead of begin()?


Bo Persson

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Deriving from concrete types like std::list Urs Thuermann <urs@isnogud.escape.de> - 2011-07-07 14:02 +0200
  Re: Deriving from concrete types like std::list Leigh Johnston <leigh@i42.co.uk> - 2011-07-07 14:04 +0100
  Re: Deriving from concrete types like std::list Alexander Bartolich <alexander.bartolich@gmx.at> - 2011-07-07 13:42 +0000
    Re: Deriving from concrete types like std::list Kai-Uwe Bux <jkherciueh@gmx.net> - 2011-07-07 22:23 +0200
      Re: Deriving from concrete types like std::list Alexander Bartolich <alexander.bartolich@gmx.at> - 2011-07-07 22:04 +0000
        Re: Deriving from concrete types like std::list Kai-Uwe Bux <jkherciueh@gmx.net> - 2011-07-08 01:16 +0200
    Re: Deriving from concrete types like std::list red floyd <redfloyd@gmail.com> - 2011-07-08 11:23 -0700
      Re: Deriving from concrete types like std::list "Balog Pal" <pasa@lib.hu> - 2011-07-08 20:30 +0200
        Re: Deriving from concrete types like std::list "Alf P. Steinbach /Usenet" <alf.p.steinbach+usenet@gmail.com> - 2011-07-08 21:16 +0200
        Re: Deriving from concrete types like std::list red floyd <redfloyd@gmail.com> - 2011-07-08 14:53 -0700
          Re: Deriving from concrete types like std::list "Balog Pal" <pasa@lib.hu> - 2011-07-09 10:33 +0200
            Re: Deriving from concrete types like std::list Leigh Johnston <leigh@i42.co.uk> - 2011-07-09 10:59 +0100
  Re: Deriving from concrete types like std::list "Bo Persson" <bop@gmb.dk> - 2011-07-07 19:12 +0200
  Re: Deriving from concrete types like std::list "MikeP" <mp011011@some.org> - 2011-07-07 15:51 -0500

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