Template help - MultiAccess

[Era Scarecrow]

On Tuesday, 8 January 2013 at 23:17:46 UTC, Philippe Sigaud wrote:
> The 'int,' part is not necessary: names a and b have a type, 
> you can determine int from CommonType!(typeof(a),typeof(b)). 
> One less field for your user.

  Here's a working example, although my updated code hasn't been 
synced yet. Naming isn't used but is small enough you don't 
really need them.

   struct S {
     struct X {int d, e;}
     X x;

     mixin(multiAccess!(int, "maxX", "@safe pure nothrow",
           "x.d > x.e", true, true, //choice, read/write
           "x.d", true,
           "x.e", false));
   }

   unittest {
     S s;
     s.x.d = 5;
     s.x.e = 10;

     //maxX returns and references ONLY the larger of the two.
     assert(s.maxX == 10);
     s.maxX = 15;
     assert(s.maxX == 15);
     assert(s.x.d == 5 && s.x.e == 15);
   }

  In this case, d & e are both strings, and returning a string 
wouldn't work (with an int). Choice can be replaced with a 
function (or lambda?).

  I think it's clear to see how these can be used.