Accessing Private Fields from Outside

[Mehrdad]

On 5/17/2011 5:13 PM, Robert Jacques wrote:
> On Tue, 17 May 2011 19:47:29 -0400, Mehrdad <wfunction at hotmail.com> 
> wrote:
>
>> Is there any (hacky) way of accessing a private field from outside a 
>> data type? (The equivalent of reflection in managed languages.)
>>
>> I'm trying to write a piece of marshaling code that needs access to a 
>> data type's fields, but can't access them because it's not allowed 
>> to. :(
>
> The short answer:
> T.tupleof works for anything that you have the source to, but doesn't 
> support polymorphism out of the box.
>
> The long answer (from my json library):
>     static Value from(T)(T value) {
>         static if(is(T == class) ) if( value is null ) return 
> Value(Null.init);
>     //...
>         static if(is(T == struct) || is(T == class)) {
>             Value[string] result;
>             foreach(i,v;value.tupleof) {
>                 result[value.tupleof[i].stringof["value.".length..$]]  
> = from(v);
>             }
>             return Value( result );
>         }
>         //..
>     }
>
> P.S. Are you marshaling to/from an open format or something proprietary?
T.tupleof has a problem though: It doesn't seem to let me actually 
access the value; it just give me a tuple I can't do anything with. Your 
example only gets the name of the field, but you never actually seem to 
access it.

(P.S.: I'm trying to marshal from/to Windows data structures, so I guess 
it's kinda both?)