why use parenthsis ?

Question

4.09/5 (3 votes)

See more:

#define BEGIN_MSG_MAP(theClass) \
public: \
BOOL ProcessWindowMessage(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam, LRESULT& lResult, DWORD dwMsgMapID = 0) \
{ \
BOOL bHandled = TRUE; \
(hWnd); \
(uMsg); \
(wParam); \
(lParam); \
(lResult); \
(bHandled); \
switch(dwMsgMapID) \
{ \
case 0:

Posted 4-Oct-08 17:47pm

palmer77

Add a Solution

4 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

Avi Berger · Answer 1 · 2010-01-21T06:06:00

I'm going to try to synthesis three other answers which each have an important point.

There are situations where seemingly useless parenthesis are necessary for correctness in a macro definition. («_Superman_») In the cases that you have highlighted, however, they have no significant impact on how the preprocessor handles the code. (loyal ginger) The parenthesis are present as documentation to indicate that the "do nothing" expressions that will likely be optimized out by the compiler were put in for a reason. (me) That reason is to suppress compiler warnings about unused values. ( KarstenK )

KarstenK · Answer 2 · 2008-10-06T23:23:00

Solution 1

to make the compiler silent about the unused values.

I make that BOOL ProcessWindowMessage(HWND /*hWnd*/,...

Posted 6-Oct-08 23:23pm

KarstenK

«_Superman_» · Answer 3 · 2010-01-21T02:00:00

Solution 3

Go through the following links -
http://everything2.com/title/Seemingly+useless+parenthesis+in+%2523define+macros[^]
http://docs.freebsd.org/info/cpp/cpp.info.Macro_Parentheses.html[^]
http://www.cprogramming.com/tutorial/cpreprocessor.html[^]

Posted 21-Jan-10 2:00am

«_Superman_»

loyal ginger · Answer 4 · 2010-01-20T10:42:00

Solution 2

In my opinion, there is no need for the parenthsis around those variables. So from the compiler point of view, they are no different from those without parenthsis.

So to your question, why use parenthsis, the answer is "because he is crazy ;P !"

Posted 20-Jan-10 10:42am

loyal ginger