std::chrono::operator<< (std::chrono::duration)

 

C++

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duration (C++11) time_point (C++11) time_of_day (C++20)	clock_time_conversion (C++20) clock_cast (C++20)
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day (C++20) month (C++20) year (C++20) weekday (C++20) operator/ (C++20) year_month_day (C++20) year_month_day_last (C++20) year_month_weekday (C++20) year_month_weekday_last (C++20)	weekday_indexed (C++20) weekday_last (C++20) month_day (C++20) month_day_last (C++20) month_weekday (C++20) month_weekday_last (C++20) year_month (C++20)
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C-style date and time

 

std::chrono::duration

Member functions
duration::duration
duration::operator=
duration::count
duration::zero
duration::min
duration::max
duration::operator+duration::operator-
duration::operator++duration::operator--
duration::operator+=duration::operator-=duration::operator*=duration::operator/=duration::operator%=
Non-member functions
operator+operator-operator*operator/operator% operator==operator!=operator<operator<=operator>operator>= operator<< (C++20) to_stream (C++20)	common_type duration_cast floor (C++17) ceil (C++17) round (C++17) abs (C++17) operator""h (C++14) operator""min (C++14) operator""s (C++14) operator""ms (C++14) operator""us (C++14) operator""ns (C++14) from_stream (C++20)
Helper classes
treat_as_floating_point duration_values

 

Defined in header <chrono>
template <class CharT, class Traits, class Rep, class Period> std::basic_ostream<CharT, Traits>&     operator<<(std::basic_ostream<CharT, Traits>& os,                const std::chrono::duration<Rep, Period>& d);		(since C++20)

Inserts a textual representation of d into os. The behavior is undefined if CharT is neither char or wchar_t, or if Rep is neither a floating-point type nor a integral type with conversion rank equal to or greater than short.

Behaves as if it forms a std::basic_string<CharT, Traits> str initially consisting of the characters in std::to_string(d.count()) (if CharT is char) or std::to_wstring(d.count()) (if CharT is wchar_t). Appends to str a suffix based on Period::type according to the following table, and inserts str into the stream with os << str;.

Period::type	Suffix
std::atto	as
std::femto	fs
std::pico	ps
std::nano	ns
std::micro	µs (U+00B5)
std::milli	ms
std::centi	cs
std::deci	ds
std::ratio<1>	s
std::deca	das
std::hecto	hs
std::kilo	ks
std::mega	Ms
std::giga	Gs
std::tera	Ts
std::peta	Ps
std::exa	Es
std::ratio<60>	min
std::ratio<3600>	h
None of the above, and Period::type::den == 1	[num]s
None of the above	[num/den]s

For the last two rows of the table, num and den in the suffix are Period::type::num and Period::type::den formatted as a decimal number with no leading zeroes, respectively.

If CharT has a 8-bit representation, the implementation is encouraged to encode "µs" as UTF-8; otherwise UTF-16 or UTF-32 is encouraged. The implementation may also substitute other encodings, include "us".

Return value

A reference to the stream, i.e., os.

Notes

d.count() is formatted using the rules of std::to_string/std::to_wstring. In particular, if Rep is a floating-point type, it is always formatted with 6 digits after the decimal point, and the number of significant digits in the resulting string may be zero if d.count() is small.

See also

to_stream (C++20)	outputs a duration into a stream according to the provided format (function template)
operator<<operator>>	performs stream input and output on strings (function template)
to_string (C++11)	converts an integral or floating point value to string (function)
to_wstring (C++11)	converts an integral or floating point value to wstring (function)