Hello,
This morning I had an idea how to write Scalable Software in general.
Unfortunately with Delphi 2007 it can't be done because it does not support
operating overloading for classes, or record inheritance (records do have
operator overloading)
The idea is to write a generic integer class with derived integer classess
for 8 bit, 16 bit, 32 bit, 64 bit and 64 bit emulated.
Then at runtime the computer program can determine which derived integer
class is needed to perform the necessary calculations.
The necessary integer class is instantiated and assigned to a generic
integer class variable/reference and the generic references/variables are
used to write the actual code that performs the calculations.
Below is a demonstration program, it's not yet completely compiling, but
it's getting close.
// TestWritingScal ableSoftware.cp p : Defines the entry point for the console
application.
//
#include "stdafx.h"
class TSkybuckGeneric Integer
{
};
class TSkybuckInt32 : public TSkybuckGeneric Integer
{
private:
int mInteger;
public:
// constructor with initializer parameter
TSkybuckInt32( int ParaValue );
// add operator overloader
TSkybuckInt32& operator+( const TSkybuckInt32& ParaSkybuckInt3 2 );
void Display();
};
class TSkybuckInt64 : TSkybuckGeneric Integer
{
private:
long long mInteger;
public:
// constructor with initializer parameter
TSkybuckInt64( long long ParaValue );
// add operator overloader
TSkybuckInt64& operator+( const TSkybuckInt64& ParaSkybuckInt6 4 );
void Display();
};
//
// TSkybuckInt32
// constructor
TSkybuckInt32:: TSkybuckInt32( int ParaValue )
{
mInteger = ParaValue;
}
// add operator overloader
TSkybuckInt32& TSkybuckInt32:: operator+ ( const TSkybuckInt32&
ParaSkybuckInt3 2 )
{
mInteger = mInteger + ParaSkybuckInt3 2.mInteger;
return *this;
}
void TSkybuckInt32:: Display()
{
printf( "%d \n", mInteger );
}
//
// TSkybuckInt64
//
// constructor
TSkybuckInt64:: TSkybuckInt64( long long ParaValue )
{
mInteger = ParaValue;
}
// add operator overloader
TSkybuckInt64& TSkybuckInt64:: operator+ ( const TSkybuckInt64&
ParaSkybuckInt6 4 )
{
mInteger = mInteger + ParaSkybuckInt6 4.mInteger;
return *this;
}
void TSkybuckInt64:: Display()
{
printf( "%lu \n", mInteger );
}
int _tmain(int argc, _TCHAR* argv[])
{
long long FileSize;
long long MaxFileSize32bi t;
// must write code like this to use constructor ? can't just declare
a,b,c ?
TSkybuckInt32 A32 = TSkybuckInt32( 30 );
TSkybuckInt32 B32 = TSkybuckInt32( 70 );
TSkybuckInt32 C32 = TSkybuckInt32( 0 );
C32 = A32 + B32;
C32.Display();
TSkybuckInt64 A64 = TSkybuckInt64( 30 );
TSkybuckInt64 B64 = TSkybuckInt64( 70 );
TSkybuckInt64 C64 = TSkybuckInt64( 0 );
C64 = A64 + B64;
C64.Display();
FileSize = 1024; // kilobyte
FileSize = FileSize * 1024; // megabyte
FileSize = FileSize * 1024; // gigabyte
FileSize = FileSize * 1024; // terrabyte
MaxFileSize32bi t = 1024; // kilobyte
MaxFileSize32bi t = MaxFileSize32bi t * 1024; // megabyte
MaxFileSize32bi t = MaxFileSize32bi t * 1024; // gigabyte
MaxFileSize32bi t = MaxFileSize32bi t * 4; // 4 gigabyte
if (FileSize < MaxFileSize32bi t)
{
TSkybuckGeneric Integer AGeneric = TSkybuckInt32( 30 );
TSkybuckGeneric Integer BGeneric = TSkybuckInt32( 70 );
TSkybuckGeneric Integer CGeneric = TSkybuckInt32( 0 );
} else
{
TSkybuckGeneric Integer AGeneric = TSkybuckInt64( 30 );
TSkybuckGeneric Integer BGeneric = TSkybuckInt64( 70 );
TSkybuckGeneric Integer CGeneric = TSkybuckInt64( 0 );
}
CGeneric = AGeneric + BGeneric;
CGeneric.Displa y();
while (1)
{
}
return 0;
}
Probably minor compile issue's remain:
Error 1 error C2243: 'type cast' : conversion from 'TSkybuckInt64 *__w64 '
to 'const TSkybuckGeneric Integer &' exists, but is inaccessible
y:\cpp\tests\te st writing scalable software generic math\version
0.01\testwritin gscalablesoftwa re\testwritings calablesoftware \testwritingsca lablesoftware.c pp
152
Error 2 error C2243: 'type cast' : conversion from 'TSkybuckInt64 *__w64 '
to 'const TSkybuckGeneric Integer &' exists, but is inaccessible
y:\cpp\tests\te st writing scalable software generic math\version
0.01\testwritin gscalablesoftwa re\testwritings calablesoftware \testwritingsca lablesoftware.c pp
153
Error 3 error C2243: 'type cast' : conversion from 'TSkybuckInt64 *__w64 '
to 'const TSkybuckGeneric Integer &' exists, but is inaccessible
y:\cpp\tests\te st writing scalable software generic math\version
0.01\testwritin gscalablesoftwa re\testwritings calablesoftware \testwritingsca lablesoftware.c pp
154
Error 4 error C2065: 'CGeneric' : undeclared identifier y:\cpp\tests\te st
writing scalable software generic math\version
0.01\testwritin gscalablesoftwa re\testwritings calablesoftware \testwritingsca lablesoftware.c pp
157
Error 5 error C2065: 'AGeneric' : undeclared identifier y:\cpp\tests\te st
writing scalable software generic math\version
0.01\testwritin gscalablesoftwa re\testwritings calablesoftware \testwritingsca lablesoftware.c pp
157
Error 6 error C2065: 'BGeneric' : undeclared identifier y:\cpp\tests\te st
writing scalable software generic math\version
0.01\testwritin gscalablesoftwa re\testwritings calablesoftware \testwritingsca lablesoftware.c pp
157
How to solve the remaining issue's ?
Bye,
Skybuck.
