literals

This question already has an answer here: Passing a string literal as a parameter to a C++ template class 12 answers I'm trying to find a comfortable way to pass string literals as template arguments. I'm not caring about supporting the widest possible number of compilers, I'm using the latest version of g++ with --std=c++0x . I've tried a lot of possible solutions but all have disappointed me. I'm sort of giving up, but first I'd like to know why a couple of them failed. Here they are: #include <iostream> #include <string> using namespace std; struct String { char const *m_sz; constexpr

Consider: struct str {}; str operator"" _X(long double d) { return str(); } This compiles fine with g++ 4.7.2 Wall std=c++11 but now if I give a double : str operator"" _X(double d) { return str(); } I get the following error message: main.cpp|3|error: 'str operator"" _X(double)' has invalid argument list What is the problem ? Has this something to do with "It is not possible to redefine the meaning of a built-in literal suffix" (Stroustrup FAQ) ? Can you think of a workaround ? What is the problem? The problem is that the Standard forbids it. Per paragraph 13.5.8./3 of the C++11 Standard on

I've a script which reads temperature data: def get_temp(socket, channels): data = {} for ch in channels: socket.sendall('KRDG? %s\n' % ch) time.sleep(0.2) temp = socket.recv(32).rstrip('\r\n') data[ch] = float(temp) Sometimes, the script fails on the line which converts the values to float: File "./projector.py", line 129, in get_temp data[ch] = float(temp) ValueError: invalid literal for float(): +135.057E+0 +078.260E+0 +00029 but this is NOT an invalid literal. If I enter this into any python shell, float(+135.057E+0) then it correctly returns 135.057. So what is the problem? I would all

Delphi strings use single quotes, for example ' a valid string '. How does one specify the ' character within a literal string? How would one refer to the null byte (Unicode code point U+0000 )? Jamie To add a single quote to a string, you include two ' marks e.g. str := '''test string'''; Writeln(str) In the string above, you have the normal single quotation to start a string and then two for the single quote. Same goes for the end of the string. You can also use # followed by a number for other escape character e.g. For a new line: str := 'Newline' + #13 + #10 or just str := 'Newline'#13#10