Proto for Boost mailing list page: Re: [proto] Visitor Design Pattern

Subject: Re: [proto] Visitor Design Pattern
From: Eric Niebler (eric_at_[hidden])
Date: 2010-10-26 01:03:23

On 10/25/2010 10:01 PM, Joel.Falcou_at_[hidden] wrote:
> 
>> There, that's better. I don't think I'll mess with it any more. Go ahead
>> and use it, Thomas.
> 
> just a small question: what if I need a transform that use external data ?
> in nt2, we have thsi compute trnsform that recursively eats the AST and
> call the approprite function passing a n dimension position tuple as a
> data.
> 
> I guess I could pass it as a state but will we have any other alternative ?

You could pass it as state or bundle it with the external transforms.
All you need is a nested when template. Does that help?

-- 
Eric Niebler
BoostPro Computing
http://www.boostpro.com