Re: Setting PropertySheet Title (Wizard mode)

"John H." <>
Thu, 8 Apr 2010 10:34:26 -0700 (PDT)
Joseph M. Newcomer wrote:

John H. wrote:

// In the foo.h:
void print_x(int num_times);
// In the foo.cpp:
#include "foo.h"
#include <iostream>
void print_x(int const num_times)

This normally results in an error from the compiler because the forward reference in the
header file conflicts with the definition. That would be 'const int' not 'int const'.

I know you know that they are the same, but just to clarify for
readers who might not, declaring a type as "int const" and "const int"
has the same semantic effect. It is really a matter of style. As
such, it is best to stick with whatever style is being used already in
the software project. For new projects, I prefer to put the const
after the int. This way when a coder is trying to determine what
exactly a "int setValues(Values const * const v) const { ... }" means,
they can use one rule: const refers to the thing that precedes it.
Historically, "const int" is the more commonly used style. However I
do see the "int const" style being used a little more, for instance
the C++ FAQ Lite section that talks about const recently switched from
"const int", to "int const" style. Readers interested in learning
more on this might check out
for more info.


   for(int i=0; i<num_times; ++i)
       std::cout << 'x';

This is the idea I was trying to say when I said put const in the
definition but not the declaration.

I knew that, and that's why I said it wouldn't work.

Here, from the caller's point of
view, it seems like an irrelevant detail on whether num_times is a
const parameter or not. The parameter is copied so whatever they
passed cannot be modified anyways. The function should produce the
same result either way. The fact that the implementation doesn't
modify num_times is really something only of interest to the
implementation. A implementation could in fact modify num_times and
still be correct, something like the following (untested):

Which would be fine if that's the way the language and compilers worked, but that isn't
how they work.

For the point I was trying to make, if I am understanding things
correctly, C++98, C++03 8.3.5/3 and C++0x draft 8.3.5/5 say that it is
legal: "Such cv-qualifiers affect only the definition of the parameter
within the body of the function; they do not affect the function
type." Also, VC++ 6, 2008 and 2010 RC seem work this way.

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