Eric Niebler wrote:
This concerns all boost developers. Please read!
I have just added documentation for how to deal with min/max in boost code. I have added it to the "Boost Library Requirements and Guidelines" document (boost/more/lib_guide.htm). That seemed the appropriate place, but it might be hard to find. If anyone thinks this belongs in a more prominent place, please suggest one.
I want to thank Eric for doing all the work, and for documenting it, in order to solve this problem. I would like to think that compiler vendors, most notably Microsoft, may have learned not to define C/C++ macros with lowercase letters. I am aware of macros like MessageBox to MessageBoxA or MessageBoxW depending if UNICODE is defined or not in the windows.h header files, but even in these cases inline function declarations forwarding the parameters to the correct function would have solved the problem much better. Of course I am also aware that .NET puts everything in namepaces and classes, and that this is the future as far as Microsoft is concerned for Windows programming. I am hoping that ideas, and perhaps implementations for all I know, which have been presented to the C++ committee for namespace-like macros will make such a problem obsolete in the future, and we can all look back and laugh that such a problem as the min/max one with windows.h header file actually needed to be solved in the days of 2004 C++ programming, much as we do now that a time actually existed where programmers had to worry about a 640K limit on IBM-like PCs. Nonetheless, thanks for all your work on this.
For reference, here is the text I have added:
---- Make sure your code compiles in the presence of the min() and max() macros. Some platform headers define min() and max() macros which cause some common C++ constructs to fail to compile. Some simple tricks can protect your code from inappropriate macro substitution:
* If you want to call std::min() or std::max():
o Use (std::min)(a,b) if you do not require argument-dependent look-up. o Use boost::std_min(a,b) if you do require argument-dependent look-up. boost::std_min() delegates to std::min().
* If you want to call std::numeric_limits<int>::max(), use (std::numeric_limits<int>::max)() instead.
* If you want to call a min() or max() member function, instead to doing obj.min(), use (obj.min)().
* If you want to declare or define a function or a member function named min or max, then you must use the BOOST_PREVENT_MACRO_SUBSTITUTION macro. Instead of writing int min() { return 0; } you should write int min BOOST_PREVENT_MACRO_SUBSTITUTION () { return 0; } This is true regardless if the function is a free (namespace scope) function, a member function or a static member function, and it applies for the function declaration as well as the function definition.