ostream

I want to define MyOStream which inherits publicly from std::ostream. Let's say I want to implement my own ofstream. How can this be done? I'll be glad for any help, coded example or any relevant link... thanks! I don't understand exactly what you're trying to accomplish here. User code shouldn't inherit from the streams themselves, as the streams are intended to provide a generalized locale specific conversion/"stringizing" facility. If you're trying to use an ostream which can write to a new buffer location (i.e. a gzip stream), then one should generally inherit from basic_streambuf instead,

I am trying to create a c++ ostream for educational reasons. My test will be creating an ostream that acts like a ofstream would except instead of writing to a file it would write to a deque or vector container. As it is for education, as you say, i will show you how i would do such a thingy. Otherwise, stringstream is really the way to go. Sounds like you want to create a streambuf implementation that then writes to a vector / deque. Something like this (copying from another answer of me that targeted a /dev/null stream ): template<typename Ch, typename Traits = std::char_traits<Ch>, typename

Today I made a small typo in my program, and was wandering why I wasn't getting any output, although the program compiled fine. Basically it reduces to this: #include <iostream> int main() { std::cout < "test"; // no << but < } I have absolutely no idea what kind of implicit conversion is performed here so the program still compiles (both g++4.9.2 and even g++5). I just realized that clang++ rejects the code. Is there a conversion to void* being performed (cannot think of anything else)? I remember seeing something like this, but I thought it was addressed in g++5, but this doesn't seem to be

I want a ostream with a prefix at the beginning of every line redirected on cout; I try this: #include <iostream> #include <thread> class parallel_cout : public std::ostream { public: parallel_cout(std::ostream& o):out(o){} template <typename T> std::ostream& operator<< (const T& val) { out << "prefix " << val; return *this; } std::ostream& out; }; int main() { parallel_cout pc(std::cout); pc<<"a\nb"<<"c\n"; } but i have in output prefix a b without c. why this? The way you modify the behavior of std::ostream is not by overloading any of the output operators! Instead, you derive a class from

By definition taken from: http://www.cplusplus.com/reference/iostream/ostream/flush/ , it is not clear why the function exists, and for what purpose you would use it for. Why not call flush(), every time your write to the stream? Mysticial In all likelihood, the word flush comes from exactly what you'd flush in real-life. A toilet... So let's try a toilet analogy: Flushing every time a new one drops into the bowl is very time-consuming and a complete waste of water. That's a big problem today where everyone's trying to be environmentally friendly. So what do you do instead? You buffer it by

well basically it should list all the vector coords in this kind of format : (x, y, z) but at the moment it does like this (x, y, z, ) easiest way would be using if in the for cycle, but can i substract a small piece of string from the out variable? my code: template <unsigned short m> std::ostream& operator<<(std::ostream& out, const Vector<m>& v) { out << "("; for(int i = 0; i < m; i++) { out << v.coords[i] << ", "; } out << ")"; return out; } That isn't possible. Another possibility: moving out of the loop the output of the first or the last coordinates. Then there is no need of an if (or

i need to implement a number class that support operator << for output. i have an error: "identifier "ostream" is undefined" from some reason eventhough i included and try also here the header file: Number.h #ifndef NUMBER_H #define NUMBER_H #include <iostream> class Number{ public: //an output method (for all type inheritance from number): virtual void show()=0; //an output operator: friend ostream& operator << (ostream &os, const Number &f); }; #endif why the compiler isnt recognize ostream in the friend function? You need to fully qualify the name ostream with the name of the namespace that

When creating formatted output for a user defined type it is often desirable to define custom formatting flags. For example, it would be nice if a custom string class could optionally add quotes around the string: String str("example"); std::cout << str << ' ' << squotes << str << << ' ' << dquotes << str << '\n'; should produce example 'example' "example" It is easy enough to create manipulators for changing the formatting flags themselves: std::ostream& squotes(std::ostream& out) { // what magic goes here? return out; } std::ostream& dquotes(std::ostream& out) { // similar magic as above