[EMAIL PROTECTED] writes: > I've read multiple posts about how to get the 'tolower' function to > work in gcc. From what I understand, the problem is that there are two > versions - you must cast to specify which version you want to use. > > transform(tempString.begin(),tempString.end(),tempString.begin(), > (int(*)(int))std::tolower);
Thanks for following my request to change into a g++ group. Here's my "threatened" information on why what you are attempting to do probably isn't a good idea: You are attempting to invoke the 1 argument verison of std::tolower(). That's the version C++ inherits from C. As most <cctype> functions, std::tolower() expects its argument to either have the value -1 or a value in the range representable by unsigned chars, i.e. 0..UCHAR_MAX; otherwise, the program has undefined behavior. If your char type is signed, and tempString contains characters with negative codes, the requirement imposed by std::tolower() will not be met in the above call to std::transform() (resp. a working version thereof). If your program uses an ASCII based character encoding, such as an ISO-8859 (or "ANSI") encoding, everyday characters such as äöüéàéñ do have negative codes. > This works with gcc, but not with MS Visual Studio 2003. It only works > with MS Visual Studio 2003 if you remove the std::. "works" and "doesn't work" are very vague. What error messsage do you get? > I'm not quite sure why this is, but I read that there are two versions > of tolower. One is the global namespace, and comes from ctype.h, and > the other one is in the std namespace. Unfortunately, the situation is more complicated: - <cctype> declares the 1 argument version of std::tolower() - <locale> declares the 2 argument version of std::tolower() - in C++, <ctype.h> works like <cctype> but adds a using declaration for std::tolower in the global namespace And in reality, C++ implemetations often don't implement the 3rd item correctly. So the best thing IMHO is to not #include <ctype.h> in new code and rely on the tolower() overloads in namespace std. > This link (http://www.thescripts.com/forum/thread161158.html) states > that std::tolower takes two arguments, not one. This link > (http://www.cplusplus.com/ reference/clibrary/cctype/tolower.html) > shows that the tolower in cctype.h takes a single argument. I am > also aware that transform must take a binary argument. There is no such thing as <cctype.h> in C++. It's either <cctype> or <ctype.h>. Both declare a 1 argument version of std::tolower(). > So, if the problem *is* because the std::tolower version takes 2 > arguments (and not one), this lead me to ask why it works in gcc? Please post a minimal, complete program that demonstrates your problem. Without seeing what headers you #include, your audience can only make guesses. _______________________________________________ help-gplusplus mailing list help-gplusplus@gnu.org http://lists.gnu.org/mailman/listinfo/help-gplusplus
