Eko Wahyudin wrote:
Hi, guys? I'm new in D and I come from pascal. The constructor
concept is very different, and it's very confusing for me.
I want to create some statement in D which in pascal like this.
type
TMyObjectAClass = class of TMyObject_A; // number 1
TMyObject_A = class
constructor Create(AString : String);
end;
TMyObject_B = class(TMyObject_A)
constructor Create(AString : String); override;
end;
TMyObject_C = class(TMyObject_A)
end;
- - - - - - - - - - - - - - - - -
function Foo(AClass: TMyObjectAClass): TMyObject_A;
begin
Result:= AClass.Create(AClass.ClassName); //number 2
end;
- - - - - - - - - - - - - - - - -
var
B : TMyObject_B;
C : TMyObject_C;
begin
B:= Foo(TMyObject_B); //number 3
C:= Foo(TMyObject_C);
end.
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Question 1> How I can make a data type "class of" in D language
Question 2> How to convert number 2, in D language.
Question 3> How I passing a "class type" as argument like number
3, and if D can do same thing like pascal, which one is called by
D, TMyObject_A.Create() or TMyObject_B.Create() ? In pascal It
should be call TMyObject_B.Create() first
"class of" in Delphi/OP means type or subtype of a class. You can use
template parameters in D to pass "class of":
// T : A means any type T that is equivalent to A or is subtype of A
A foo(T : A)()
{
return new T(T.stringof);
}
B b;
C c;
b = foo!B();
c = foo!C();
