Re: Automata builder -- interface

From: Vladimir Prus (ghost_at_[hidden])
Date: 2001-05-31 05:13:03

Joel de Guzman wrote:
>Aggregates need not store subjects by value. A reference is fine since we
>know that the subject has a lifetime equal to or greater than the aggregate.
>Rules<> are composed by reference in Spirit. I such cases, the aggregate
>does not own the subject(s).

There are only two choices without BNF class. 
1) Store everything by value. Problem -- duplicated information makes it hard 
to change a rule, which is desirable sometimes.
2) Store everying by reference (or pointer). Problem -- garbage collection 
needeed.

As for  "lifetime equal or greater than ..." --- it is the case with Spirit, 
but in general objects will be newd and user should not care for their 
deletion.

-- 
Regards,
Vladimir