Proposal:better COM support and DB support?

[davidl]

The idea is compile time convert DotExp to a String.

consider:
class COMBase
{
    Variant opDotExp(string field)
   {
      //do shit with COM
   }
}

COMBase mycominst;
mycominst.kk(); <-- this would actually result code  
mycominst.opDotExp("kk()") by the compiler

I don't quite like the syntax of  
mycominst.Call_My_COM_Method("Method_Name", ...)

and consider:

abstract class FieldClass
{
    Variant k;
    int opImplicitCastTo(){ throw new Exception("this is not an int  
field");};
    float opImplicitCastTo(){throw new Exception("this is not a float  
field");};
    double opImplicitCastTo(){throw new Exception("this is not a double  
field");};
    string opImplicitCastTo(){throw new Exception("this is not a string  
field");};
}

class MyIntField:FieldClass
{
    int opImplicitCastTo(){ return k.toInt;}
    this (Variant t){k = t;}
}

class MyTable
{
    FieldClass opDotExp(string field)  // compiler only comes to this when  
compiler fails to match any DotExp
    {
        Variant t;
        // get field from database and put it to variant t.
        static if (field == "MyIntField")
          return new MyIntField(t);
        else static if (field == "MyFloatField")
          return new MyFloatField(t);   // a similar helper class like  
MyIntField would be required
        else static if (field == "MyDoubleField")
          return new MyDoubleField(t);  // a similar helper class like  
MyIntField would be required
        else
          static assert(0);   // this operator should end with static  
assert(0);
    }
}


MyTable table;
table.MyIntField = 3;    // this would result actually a MyIntField object  
and if programmer implement the opAssign of MyIntField class, then it  
would be possible for programmer to handle database in a very nice  
language integrated syntax.

Yes, string mixin can handle it very well. But I still like the LINQ  
syntax.

So compile-time DotExp to a string would bring us two things very nice.
1.better COM syntax.
2.LINQ syntax available.

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