Re: [Boost-users] [fusion] simple Fusion question

Subject: Re: [Boost-users] [fusion] simple Fusion question
From: Joel de Guzman (joel_at_[hidden])
Date: 2010-11-09 21:43:03

On 11/10/2010 8:46 AM, Eric Niebler wrote:
> On 11/2/2010 8:23 AM, Joel de Guzman wrote:
>> On 11/2/2010 12:22 PM, Eric Niebler wrote:
>>>
>>> Given an mpl::vector of keys, and a fusion::vector of values, what's the
>>> easiest way to create a fusion::map?
>
> Nobody ever answered this one. It's ok, my immediate need has passed.
> I'm just curious if there's an easy way that I missed.

The easy and obvious way is the one that you described below.
It's a deficiency of Fusion that it's not doable this way
as it should be. IOTW, there's no straightforward way ATM.

>>> The obvious solution of just zipping the two sequences and passing the
>>> result to fusion::as_map doesn't work because as_map (somewhat narrowly)
>>> requires all elements to be fusion::pair, and Fusion's zip algorithm
>>> produces sequences of vector2. I'd like to see this generalized so that
>>> (a) as_map only requires sequences of 2-tuples and (b) fusion::pair
>>> meets the requirements for 2-tuples.
>>
>> Makes perfect sense. Do you have a patch?
>
> Sorry, no. I filed a feature request, instead.

Thanks, Eric.

Regards,
-- 
Joel de Guzman
http://www.boostpro.com
http://spirit.sf.net