[boost] Re: [prereview request][fsm]

From: Jeff Flinn (TriumphSprint2000_at_[hidden])
Date: 2004-05-28 08:54:34

"Johan Nilsson" <johan.nilsson_at_[hidden]> wrote in message
news:c97cum$cn2$1_at_sea.gmane.org...
>
> "Jeff Flinn" <TriumphSprint2000_at_[hidden]> wrote in message
> news:c97afd$60h$1_at_sea.gmane.org...
> >
> > "Johan Nilsson" <johan.nilsson_at_[hidden]> wrote in message
> > news:c96p5d$qlg$1_at_sea.gmane.org...
> > >
>
> [...]
>
> > matter
> > > if this is a two-step procedure:
> > > Allocate in constructors + Initialize in entry
> > > or one-step:
> > > Allocate and initialize in constructor.
> >
> > class astate : non_copyable
> > {
> >     T& mRef;
> >
> >     astate();
> >
> > public:
> >
> >     astate( T& aRef ):mRef(aRef){ aRef.somefunction(); }
> >
> >     void init( T& aRef ){ mRef = aRef; mRef.somefunction(); } // not the
> > same
> >
> > };
>
> No, of course not. I meant:
>
> // one-step
> class astate : non_copyable { ...
>     astate( T& aRef ):mRef(aRef){ aRef.somefunction(); }
> ... };
>
> versus:
>
> // two-step
> class astate : non_copyable { ...
>     astate( T& aRef ):mRef(aRef){}
>     void entry(){ mRef.somefunction(); }
> ... };

This assumes that you have access to the same information at construction
time as at the call to astate::entry (you previously were discussing
init/deinit). I was pointing out that separating out init() does in fact
come with some cost to flexibility.

Jeff Flinn