...the synergy of returns in EAX and params in EAX.

It would be fairly easy...

...Explicit module `friendship` (#43)
33  Pass value params byref (#34)
33  auto-member objects (#45...

...not be a perfect approach, but at least you *can* leave middle params as default.

...public bool isOpen() {
        return isOpen_;
    }

    /*************************************************************
     *  Write property
     *  Params:
     *      value = 110, 300, 600, 1200, 2400, 4800...

...Explicit module `friendship` (#43)
33  Pass value params byref (#34)
33  auto-member objects (#45...

...Params == function ) )
        alias Params ParameterTupleOf;
    else static if( is( Fn Params == delegate ) )
        alias ParameterTupleOf!(Params...

...passing multiple functions that accept the same params is valid.  The first will just always...

...for SciD is just that,

  double[] algo(params, double[] buffer=null, double[] workspace=null);

and...

...Explicit module `friendship` (#43)
33  Pass value params byref (#34)
33  auto-member objects (#45...

...mixin("R opCall("~
    refToParamList("" /* no leading parameter */, "Params!(C)[1 .. $]" /* types to check */, isRef!(C...