As discussed in DConf2015: Python-like keyword arguments

[Liran Zvibel via Digitalmars-d]

On Friday, 29 May 2015 at 15:16:56 UTC, Jonathan Crapuchettes 
wrote:
> Two other ways to implement the concept. The first works with 
> optional
> arguments and the other requires all arguments.
>

> unittest
> {
>     alias arg1 = namedArguments!("arg1", string);
>     alias arg2 = namedArguments!("arg2", int);
>
>     void namedArgsFunc(T...)(T arguments)
>     {
>         const vars = parseArguments!()(arguments);
>         const string one = vars.arg1;
>         const int two = vars.arg2;
>     }
>     namedArgsFunc(arg1(""), arg2(42));
>     namedArgsFunc(arg2(56), arg1("fred"));
> }
...
> Jonathan

This is a very interesting approach, but the problem is that the 
person writing the function has to work to give support.
I think we should try to create a wrapper function taking the 
original function as (alias F) that leverages 
ParameterIdentifierTuple , ParameterTypeTuple and 
ParameterDefaultValueTuple to generate the namedArguments 
automatically.

Also, we could actually make this a Functor/Callback object that 
has already created members that give you easy access to the 
types of the named arguments. This way, we can even conceive a 
way to return a "partial" function with enough arguments, and 
only really call it when all the keyword arguments were actually 
provided (or enough of them were provided and the rest have 
provided a default value).

This will allow us to create a concise API that is convenient, 
and strong.

Liran