[VS2005] c++ "scope operator"

  • Thread starter Thread starter marco_segurini
  • Start date Start date
M

marco_segurini

Hi,

I am using VS 2005.

If I compile the following code only line 6 returns me an error while
line 9 returns a warning. If I comment the line 6 and debug the
program the assignments of lines {9, 11} work fine.

Why the '.' "scope operator" is accepted in line 9 and not in line 6?

thanks.
Marco.

//-----------
using namespace System;

int main()
{
double d;
d = Math.Cos(1.0); // line 6
d = Math::Cos(1.0);

d = Math.PI; // line 9
d = 0;
d = Math::PI; // line 11
}

------ Rebuild All started: Project: scope, Configuration: Debug Win32
------
Deleting intermediate and output files for project 'scope',
configuration 'Debug|Win32'
Compiling...
stdafx.cpp
Compiling...
scope.cpp
scope.cpp(6) : warning C4832: token '.' is illegal after UDT
'System::Math'
scope.cpp : see declaration of 'System::Math'
scope.cpp(6) : error C2275: 'System::Math' : illegal use of this type
as an expression
scope.cpp : see declaration of 'System::Math'
scope.cpp(9) : warning C4832: token '.' is illegal after UDT
'System::Math'
scope.cpp : see declaration of 'System::Math'
AssemblyInfo.cpp
Generating Code...
Build log was saved at "file://e:\Project C++ NET
2005\Prove\scope\scope\Debug\BuildLog.htm"
scope - 1 error(s), 2 warning(s)
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========
 
Because .PI is a 'structure' member and Cos is static function member
Hi,

I am using VS 2005.

If I compile the following code only line 6 returns me an error while
line 9 returns a warning. If I comment the line 6 and debug the
program the assignments of lines {9, 11} work fine.

Why the '.' "scope operator" is accepted in line 9 and not in line 6?

thanks.
Marco.

//-----------
using namespace System;

int main()
{
double d;
d = Math.Cos(1.0); // line 6
d = Math::Cos(1.0);

d = Math.PI; // line 9
d = 0;
d = Math::PI; // line 11
}

------ Rebuild All started: Project: scope, Configuration: Debug Win32
------
Deleting intermediate and output files for project 'scope',
configuration 'Debug|Win32'
Compiling...
stdafx.cpp
Compiling...
scope.cpp
scope.cpp(6) : warning C4832: token '.' is illegal after UDT
'System::Math'
scope.cpp : see declaration of 'System::Math'
scope.cpp(6) : error C2275: 'System::Math' : illegal use of this type
as an expression
scope.cpp : see declaration of 'System::Math'
scope.cpp(9) : warning C4832: token '.' is illegal after UDT
'System::Math'
scope.cpp : see declaration of 'System::Math'
AssemblyInfo.cpp
Generating Code...
Build log was saved at "file://e:\Project C++ NET
2005\Prove\scope\scope\Debug\BuildLog.htm"
scope - 1 error(s), 2 warning(s)
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========
Click to expand...


--
Jacobo Rodríguez Villar

TyphoonLabs Lead Programmer

http://www.typhoonlabs.com
 
Jacobo said:
Because .PI is a 'structure' member and Cos is static function member
Click to expand...

Thanks Jacobo,

the Intellisense tells me that PI and Cos are both 'static members' of
the Math class. So like happens using a not managed c++ class only one
scope syntax has to be permitted (::).

Bye.
Marco.
 
Marco,
Thanks Jacobo,

the Intellisense tells me that PI and Cos are both 'static members' of
the Math class.
Click to expand...

They are.
So like happens using a not managed c++ class only one
scope syntax has to be permitted (::).
Click to expand...

Well, as it should, since they are static (and there's no instance to call
it from). The code is incorrect in that it tried to use the '.' operator to
reference Math::PI.
 
Back
Top