Proto for Boost mailing list page: Re: [proto] How to customize an expression in an EDSL , so as to make a deep copy of it?

Subject: Re: [proto] How to customize an expression in an EDSL , so as to make a deep copy of it?
From: Bart Janssens (bart_at_[hidden])
Date: 2015-12-22 06:57:01

Hi Masa,

The problem is that you were not really building a proto expression, but
just calling your DifferenceOperator directly. You can create a proper
proto terminal in your domain using:
ExprWrapper<boost::proto::terminal<DifferenceOperator>::type> const opr =
{{}};

Once that is done, only the deep copy compiles, but you need a proper
grammar for evaluation to work, and a << overload for printing and starting
evaluation. The fixed code with a small start of the grammar is attached.

p.s. It's awfully quiet on this list, is it still the place to discuss
Proto?

Cheers,

Bart

On Mon, Dec 14, 2015 at 12:48 PM Masakatsu ITO(伊藤) <itoh.masakatsu_at_[hidden]>
wrote:

> Hello,
>
> I'm trying to make an EDSL for finite volume method,
> which translates a formula of the method into
> executable code.
>
> Now I've confirmed that such a formula
>
>      std::cout << MyEDSL::opr( 0.1, 0.1) + 1.0 << std::endl;
>
> can be compiled and prints out the correct answer.
>
>