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This is fine as far as it goes, although IMO it adds a level of abstraction that is unnecessary (i.e. I still need to translate this on the fly as I read the document, although what you've shown is quite intuitive.
Which is the exact reasons I don't some of the more basic STL functions such as for_each. Let's just say I disagree with Scott Meyers on every point. Even he admits functions such as for_each can obscure code.
Tim Smith
I know what you're thinking punk, you're thinking did he spell check this document? Well, to tell you the truth I kinda forgot myself in all this excitement. But being this here's CodeProject, the most powerful forums in the world and would blow your head clean off, you've got to ask yourself one question, Do I feel lucky? Well do ya punk?
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Tim Smith wrote:
Let's just say I disagree with Scott Meyers on every point.
On *every* point ? I believe he advocates the typedef's we are discussing, actually.
Tim Smith wrote:
Which is the exact reasons I don't some of the more basic STL functions such as for_each.
I don't think for_each obscures code to the degree that typedefs do, and in both cases it obscures it for people other than the author.
Personally I don't use for_each that much either, I think the main reason I've used it is to delete pointers in my destructor. It is also true that my use of STL has not needed too many algorithms.
Christian
The tragedy of cyberspace - that so much can travel so far, and yet mean so little.
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That's why I always believe that if a programmer cannot write a decent for loop him/herself s/he shouldn't be programming at all... 
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execuseme, I'm not good speak english.
I have one problem in WinCE..
I don't send document or text to printer in Embedded MFC .
I want send japan's and arabic character to IrDA printer..
please help me..
my mail adress: mgencer99@hotmail.com
MFC
MFC
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does anyone know why this linking error is happening:
error LNK2005: "public: __thiscall CMove::CMove(int &,int &)" (??0CMove@@QAE@AAH0@Z) already defined in Computer.obj
i have define my inclusion guards and everything but this error still keeps coming up. can anyone tell me wats the cause of this linking error...  well, anyways, thank for you help 
john
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Make it inline
inline CMove::CMove(int&, int& )
{
}
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CMove::CMove must be defined in your code twice. The error suggests that it is in Computer.cpp and and in another file.
Where is the CMove constructor body, is it in Computer.cpp?
If you are certain it isn't defined twice, try doing a rebuild all.
Michael
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Guys
As a few of you might be aware of, I am trying ATL out.
Say I have a function like this :-
STDMETHODIMP CIniEdit::TestMethod(BSTR *pbstr)
{
OLECHAR tmpString[512];
wcscpy(tmpString,L"Nish is learning ATL");
*pbstr=SysAllocString(tmpString);
return S_OK;
}
and from ASP or VB say, I do this :-
Dim x
Set x = CreateObject("SIMPLE.SimpleStuff")
MsgBox x.TestMethod()
Set x = Nothing
You'd think, all was fine. But to my utmost horror I suddenly realized that I had happily allocated a string using SysAllocString, but I am not calling SysFreeString.
Horror of horrors!!!!
What is the work-around to this, dear friends?
Am I doomed to be stuck among the ultimate dangers of memory leaks?
Writing another function just to free the string seems pathetic. And I am sure that from ASP/VB this function might be called several times, thus resulting in a memory leak, each single time
Nish 
It's seven o'clock
On the dot
I'm in my drop top
Cruisin' the streets - Oh yeah
I got a real pretty, pretty little thing that's waiting for me
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An out parameter should not be assumed to contain anything valid and should be initialised before use ( for exmaple, set pointers to NULL). Responsiblity for freeing the memory belongs to the calling function. All of this is laid out in COM, and I believe there are special functions for allocating the memory and freeing it as well, but I forget them ( I'm a beginner at this, too ).
Christian
The tragedy of cyberspace - that so much can travel so far, and yet mean so little.
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Nish [BusterBoy] wrote:
Am I doomed to be stuck among the ultimate dangers of memory leaks?
No,It's ok Nish.
In COM, it is the client's responsibility to free resources allocated by a server at a client's request.
Mazy
"So,so you think you can tell,
Heaven from Hell,
Blue skies from pain,...
How I wish,how I wish you were here."
Wish You Were Here-Pink Floyd-1975
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Mazdak wrote:
In COM, it is the client's responsibility to free resources allocated by a server at a client's request.
oh?
But how can I free resources using VB or ASP???
They dont have a delete operator/function
Nish
It's seven o'clock
On the dot
I'm in my drop top
Cruisin' the streets - Oh yeah
I got a real pretty, pretty little thing that's waiting for me
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Nish [BusterBoy] wrote:
how can I free resources using VB or ASP???
I don't know about VB or ASP,but when I use C++ or MFC as clients I use SysFreeStrnig() for those BSTR.
And After all I use Release() for my component before CoUninitialize() so if those things exist in VB or ASP,I think the operation of FREEDOM happend in Release().
Mazy
"So,so you think you can tell,
Heaven from Hell,
Blue skies from pain,...
How I wish,how I wish you were here."
Wish You Were Here-Pink Floyd-1975
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Just another hint Nish:
If you use _bstr_t you'll get rid of those allocated and deallocated hell,but you don't have BSTR* .It isn't provided in _bstr_t.
Mazy
"So,so you think you can tell,
Heaven from Hell,
Blue skies from pain,...
How I wish,how I wish you were here."
Wish You Were Here-Pink Floyd-1975
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You don't need to free it, the scripting engine automatically frees it for you by calling SysFreeString (actually it calls VariantFree. That's why you use SysAllocString and not the operator new in C++.
Here is what happens from scripting engine point of view
1. Gets IDispatch interface to your object
2. Calls GetIDsOfNames to get ID of "TestMethod"
3. Calls Invoke method with that ID
4. The return value comes in pvarResult
5. Calls VariantFree to pvarResult after MsgBox function is called
6. VariantFree checks for the type of the Variant and sess that it is a BSTR and calls SysFreeString
That's the reason why you use BSTR because you have standard functions for allocating and deallocating which are known by both you and the consumer (script engine).
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Thanks 
Nish
It's seven o'clock
On the dot
I'm in my drop top
Cruisin' the streets - Oh yeah
I got a real pretty, pretty little thing that's waiting for me
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OLE automation uses only VARIANT data types. So any parameters, which are passed between your server and VB, ASP, scripting engines, or any client, which use ole automation should be VARIANT compatible. The VB runtime will simply free the resources by calling VariantClear or some similar mechanism when the resource will go out of scope.
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solon wrote:
The VB runtime will simply free the resources by calling VariantClear or some similar mechanism when the resource will go out of scope.
Cool
And thanks too
Nish
It's seven o'clock
On the dot
I'm in my drop top
Cruisin' the streets - Oh yeah
I got a real pretty, pretty little thing that's waiting for me
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I asked an expert and this is what he said:
In VB and ASP you do not need to call SysFreeString() because VB makes that call for you.
Mazy
"So,so you think you can tell,
Heaven from Hell,
Blue skies from pain,...
How I wish,how I wish you were here."
Wish You Were Here-Pink Floyd-1975
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Thanks a lot Mazy ![Rose | [Rose]](https://codeproject.freetls.fastly.net/script/Forums/Images/rose.gif)
You are a big help
Nish
It's seven o'clock
On the dot
I'm in my drop top
Cruisin' the streets - Oh yeah
I got a real pretty, pretty little thing that's waiting for me
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VARIANT v;
V_VT (&v) = VT_ENIGMA;
V_ENIGMA (&v) = ::CoCreateEnigma ();
Tim Smith
I know what you're thinking punk, you're thinking did he spell check this document? Well, to tell you the truth I kinda forgot myself in all this excitement. But being this here's CodeProject, the most powerful forums in the world and would blow your head clean off, you've got to ask yourself one question, Do I feel lucky? Well do ya punk?
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First of all, my equipment:
I use the Win2kServer OS with the following settings:
Name:iras
Workgroup: HTBL
Domain for Windows: htlpinkafeld.at
Domain for Netware: HTBl\
TestUser: testuser@htlpinkafeld.at (HTBL\testuser)
The TestUser is placed in hltpinkafeld.at\edvoschueler and uses no password
My goal is to get access to this testuser with Visual C++ 6.0 from a remote workstation (in the same network). The OS of the workstation is Win2kProf.
The MSDN which i use is the April 2001 version.
At first i tried to get the function
HRESULT ADsOpenObject(
LPWSTR lpszPathName,
LPWSTR lpszUserName,
LPWSTR lpszPassword,
DWORD dwReserved,
REFIID riid,
VOID FAR * FAR *ppObject
);
work!
And according to this the problems began!
1. I don't know how the first three parameters should look like!
2. The 5th parameter needs the library ADSIID.lib. The function needs also the library ActiveDS.lib to work right. But within these two libs declarations are redefined which means i can't execute the program! I found out that this sometimes happens, and that i should add the prefix "/force:multiple" to the menu Project\Settings...\Link\"Project Options". It works but i don't know if this is allowed!
Please help me!
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Hey Guys
Below is the funvtion i am exporting from my DLL.
bool DLLVerifySignature(BYTE *pFileNameAndPath)
This is called when a file is double clicked by rundll32 and i have put %1 at the end to pass the filepath as well. How do i pick this filename up in my dll so i can use it.
Peter
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Calling that with Rundll32 will not work. The function needs this prototype:
void CALLBACK FuncName ( HWND hwndParent, HINSTANCE hinstDLL, LPTSTR szCmdLine, int nCmdShow ); The szCmdLine param contains everything on the rundll32 command line after the function name.
--Mike--
Best score on the mini-putt game: 27
My really out-of-date homepage
Sonork - 100.10414 AcidHelm
Big fan of Alyson Hannigan and Jamie Salé.
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do i use delete object like this to prevent resource leaks???
// Destructor
CBoard::~CBoard()
{
// Delete the object to prevent resource leaks
mpPen->DeleteObject();
mpFont->DeleteObject();
// Destroys all the pointers to all objects
delete mpPen;
delete mpFont;
for (int r = 0; r < MAXROW; r++)
for (int c= 0; c < MAXCOL; c++)
delete mpGrid[r][c];
}
or i can just destroy it by deleting it or do i have to release it before i delete it when i called it like this:
// Change the Font Height and Width to the values entered
void CBoard::SetFontSize(CDC* pDC, int Height, int Width)
{
mpFont = new CFont;
VERIFY(mpFont->CreateFont(Height,Width,0,0,0,0,0,0,0,0,0,0,
DEFAULT_PITCH|FF_DONTCARE,"Tictactoe"));
VERIFY(mpDefaultFont = pDC->SelectObject(mpFont));
}
anyways, can anyone tell me if i am doing it right or what i am doing can cause memory or resource leaks... well, thank you in advance for your help
John
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The most important step is selecting the original pen/brush/font into the DC before destroying it. OTherwise you will leak GDI resources and your program will eventually kill the graphics subsystem on any non-NT based OS.
You don't need to call DeleteObject before calling delete. Delete allows you to delete the handle being encapsulated without destroying the class object.
Christian
The tragedy of cyberspace - that so much can travel so far, and yet mean so little.
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