Converting C++ code to PB

[Balthasar Indermuehle]

Hi all,

I need a primer on how to convert C++ to PB (as the subject instigates).

How do you translate the "new" keyword in a statement like this:

xyz = new XYZ(hWnd, &r1);

How do you define a class in PB, i.e. translate something like this:

class XYZ xxyyzz
{
	private:
		CNullStorage    storage;
		CMySite		site;

	public:
		HWND	hWnd;
...

}

------------------
Balt
balt at inside dot net
"It's not the end, not even the beginning of the end, but, it might be the end of the beginning!"

[Lothar Pink]

Balt,

You can't translate classes to PB, because PB doesn't support classes.
PB is, unlike C++, not an object-oriented programming language.

You might however "simulate" using classes using ...

TYPE MyClass
   MyClassVar AS LONG
   MyClassVar2 AS STRING
 
END TYPE
 
FUNCTION MyClass_Function1(c AS MyClass PTR, param1 AS LONG) AS LONG
    LOCAL lRet AS LONG
 
    lRet = @c.MyClassVar * param1
 
    FUNCTION = lRet
END FUNCTION

' this wouldn't probably work that way; it's just to show some concept how
it might work
FUNCTION MyClass_New() AS MyClass PTR
    LOCAL c AS MyClass PTR
    ' reserve memory for new instance
    
    c = VirtualAlloc(BYVAL %NULL, BYVAL SIZEOF(@c), %MEM_COMMIT)

    FUNCTION = @c
END FUNCTION

FUNCTION MyClass_Dispose(c AS MyClass PTR)
    VirtualFree BYVAL c, %MEM_RELEASE
END FUNCTION

This would simulate the following VB.NET class:

Class MyClass
    Public MyClassVar As Integer
    Public MyClassVar2 As Integer
 
    Public Function MyClassFunction1(param1 As Integer) As Integer
        Return MyClassVar * param1
    End Function
 
End Class

To access class members ...

FUNCTION PBMAIN AS LONG
    LoCAL c AS MyClass PTR
 
    c = MyClass_New()
 
    @c.MyClassVar = 500
 
    @c.MyClassVar2 = MyClass_Function1(@c, 100)
 
    MyClass_Dispose c
 
END FUNCTION

I hope that explains a bit ...

Regards

PS: You should also know, that languages like VB.NET, C++ etc., do nothing
else than "convert" the object-oriented code to something like my PB code.
Don't forget: Objects are not natively supported by the processor!
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[This message has been edited by Lothar Pink (edited August 02, 2004).]

[Robert DeBolt]

Another twist on OO programming:

http://www.allbasiccode.com/newsite/abc.cgi?ACT=DQ

Search on "oop.bas".


------------------
Regards
----------------------
Robert DeBolt
mailto:[email protected][email protected]</A>