Proto for Boost mailing list page: Re: [proto] [proto-11] expression extension

Subject: Re: [proto] [proto-11] expression extension
From: Joel Falcou (joel.falcou_at_[hidden])
Date: 2012-06-04 15:48:13

Le 04/06/2012 21:18, Eric Niebler a écrit :
> The make_expr function object takes as arguments the tag and the
> children. You can do whatever you want. If open extensibility matters,
> you can dispatch to a function found by ADL or to a template specialized
> on the tag like proto::switch_. It's up to you.

Ok perfect

> Not sure what you mean. Are you referring to the current discussion
> about having to use shared_ptr to store something? That seems unrelated
> to me.
>
> Assuming your types are efficiently movable, the default should just do
> the right thing, and your expression trees can be safely stored in local
> auto variables without dangling references. Does that help?

I was thinking of the case where we constructed a foo expression by
calling expression constructor one  into the other. I guess it fixes that.

> Proto-11 will probably take many months. I'm taking my time and
> rethinking everything. Don't hold your work up waiting for it.

No problem, just that if you need some reality check at some point we 
may provide a non trivial test case. We're doing it anyway ;)