// i_dont_like_the_default_duration_behavior.cpp ----------------------------------------------------------// // Copyright 2008 Howard Hinnant // Copyright 2008 Beman Dawes // Copyright 2009 Vicente J. Botet Escriba // Distributed under the Boost Software License, Version 1.0. // See http://www.boost.org/LICENSE_1_0.txt /* This code was extracted by Vicente J. Botet Escriba from Beman Dawes time2_demo.cpp which was derived by Beman Dawes from Howard Hinnant's time2_demo prototype. Many thanks to Howard for making his code available under the Boost license. The original code was modified to conform to Boost conventions and to section 20.9 Time utilities [time] of the C++ committee's working paper N2798. See http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2798.pdf. time2_demo contained this comment: Much thanks to Andrei Alexandrescu, Walter Brown, Peter Dimov, Jeff Garland, Terry Golubiewski, Daniel Krugler, Anthony Williams. */ #include #include #include namespace I_dont_like_the_default_duration_behavior { // Here's how you override the duration's default constructor to do anything you want (in this case zero) template class zero_default { public: typedef R rep; private: rep rep_; public: zero_default(rep i = 0) : rep_(i) {} operator rep() const {return rep_;} zero_default& operator+=(zero_default x) {rep_ += x.rep_; return *this;} zero_default& operator-=(zero_default x) {rep_ -= x.rep_; return *this;} zero_default& operator*=(zero_default x) {rep_ *= x.rep_; return *this;} zero_default& operator/=(zero_default x) {rep_ /= x.rep_; return *this;} zero_default operator+ () const {return *this;} zero_default operator- () const {return zero_default(-rep_);} zero_default& operator++() {++rep_; return *this;} zero_default operator++(int) {return zero_default(rep_++);} zero_default& operator--() {--rep_; return *this;} zero_default operator--(int) {return zero_default(rep_--);} friend zero_default operator+(zero_default x, zero_default y) {return x += y;} friend zero_default operator-(zero_default x, zero_default y) {return x -= y;} friend zero_default operator*(zero_default x, zero_default y) {return x *= y;} friend zero_default operator/(zero_default x, zero_default y) {return x /= y;} friend bool operator==(zero_default x, zero_default y) {return x.rep_ == y.rep_;} friend bool operator!=(zero_default x, zero_default y) {return !(x == y);} friend bool operator< (zero_default x, zero_default y) {return x.rep_ < y.rep_;} friend bool operator<=(zero_default x, zero_default y) {return !(y < x);} friend bool operator> (zero_default x, zero_default y) {return y < x;} friend bool operator>=(zero_default x, zero_default y) {return !(x < y);} }; typedef boost::chrono::duration, boost::nano > nanoseconds; typedef boost::chrono::duration, boost::micro > microseconds; typedef boost::chrono::duration, boost::milli > milliseconds; typedef boost::chrono::duration > seconds; typedef boost::chrono::duration, boost::ratio<60> > minutes; typedef boost::chrono::duration, boost::ratio<3600> > hours; void test() { milliseconds ms; std::cout << ms.count() << '\n'; } } // I_dont_like_the_default_duration_behavior int main() { I_dont_like_the_default_duration_behavior::test(); return 0; }