Init

cppdraft/time/hms/members.md

@@ -0,0 +1,186 @@
+[time.hms.members]
+
+# 30 Time library [[time]](./#time)
+
+## 30.9 Class template hh_mm_ss [[time.hms]](time.hms#members)
+
+### 30.9.2 Members [time.hms.members]
+
+[🔗](#itemdecl:1)
+
+`static constexpr unsigned fractional_width = see below;
+`
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8451)
+
+fractional_width is the number of fractional decimal digits
+represented by precision[.](#1.sentence-1)
+
+fractional_width has the value
+of the smallest possible integer in the range [0, 18] such thatprecision will exactly represent all values of Duration[.](#1.sentence-2)
+
+If no such value of fractional_width exists, thenfractional_width is 6[.](#1.sentence-3)
+
+[*Example [1](#example-1)*:
+
+See Table [132](#tab:time.hms.width "Table 132: Examples for fractional_­width") for some durations,
+the resulting fractional_width, and
+the formatted fractional second output of Duration{1}[.](#1.sentence-4)
+
+Table [132](#tab:time.hms.width) — Examples for fractional_width [[tab:time.hms.width]](./tab:time.hms.width)  
+
+| [🔗](#tab:time.hms.width-row-1)<br>**Duration** | **fractional_width** | **Formatted fractional second output** |
+| --- | --- | --- |
+| [🔗](#tab:time.hms.width-row-2)<br>hours, minutes, and seconds | 0 |  |
+| [🔗](#tab:time.hms.width-row-3)<br>milliseconds | 3 | 0.001 |
+| [🔗](#tab:time.hms.width-row-4)<br>microseconds | 6 | 0.000001 |
+| [🔗](#tab:time.hms.width-row-5)<br>nanoseconds | 9 | 0.000000001 |
+| [🔗](#tab:time.hms.width-row-6)<br>duration<int, ratio<1, 2>> | 1 | 0.5 |
+| [🔗](#tab:time.hms.width-row-7)<br>duration<int, ratio<1, 3>> | 6 | 0.333333 |
+| [🔗](#tab:time.hms.width-row-8)<br>duration<int, ratio<1, 4>> | 2 | 0.25 |
+| [🔗](#tab:time.hms.width-row-9)<br>duration<int, ratio<1, 5>> | 1 | 0.2 |
+| [🔗](#tab:time.hms.width-row-10)<br>duration<int, ratio<1, 6>> | 6 | 0.166666 |
+| [🔗](#tab:time.hms.width-row-11)<br>duration<int, ratio<1, 7>> | 6 | 0.142857 |
+| [🔗](#tab:time.hms.width-row-12)<br>duration<int, ratio<1, 8>> | 3 | 0.125 |
+| [🔗](#tab:time.hms.width-row-13)<br>duration<int, ratio<1, 9>> | 6 | 0.111111 |
+| [🔗](#tab:time.hms.width-row-14)<br>duration<int, ratio<1, 10>> | 1 | 0.1 |
+| [🔗](#tab:time.hms.width-row-15)<br>duration<int, ratio<756, 625>> | 4 | 0.2096 |
+
+— *end example*]
+
+[🔗](#itemdecl:2)
+
+`using precision = see below;
+`
+
+[2](#2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8502)
+
+precision isduration<common_type_t<Duration::rep, seconds::rep>, ratio<1, 10fractional_width>>
+
+[🔗](#itemdecl:3)
+
+`constexpr explicit hh_mm_ss(Duration d);
+`
+
+[3](#3)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8514)
+
+*Effects*: Constructs an object of type hh_mm_ss which represents the Duration d with precision precision[.](#3.sentence-1)
+
+- [(3.1)](#3.1)
+
+  Initializes is_neg with d < Duration​::​zero()[.](#3.1.sentence-1)
+
+- [(3.2)](#3.2)
+
+  Initializes h with duration_cast<chrono​::​hours>(abs(d))[.](#3.2.sentence-1)
+
+- [(3.3)](#3.3)
+
+  Initializes m with duration_cast<chrono​::​minutes>(abs(d) - hours())[.](#3.3.sentence-1)
+
+- [(3.4)](#3.4)
+
+  Initializes s with duration_cast<chrono​::​seconds>(abs(d) - hours() - minutes())[.](#3.4.sentence-1)
+
+- [(3.5)](#3.5)
+
+  If treat_as_floating_point_v<precision​::​rep> is true,
+ initializes ss with abs(d) - hours() - minutes() - seconds()[.](#3.5.sentence-1)
+  Otherwise, initializes ss with duration_cast<precision>(abs(d) - hours() - minutes() - seconds())[.](#3.5.sentence-2)
+
+[*Note [1](#note-1)*:
+
+When precision​::​rep is integral andprecision​::​period is ratio<1>,subseconds() always returns a value equal to 0s[.](#3.sentence-2)
+
+— *end note*]
+
+[4](#4)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8541)
+
+*Postconditions*: If treat_as_floating_point_v<precision​::​rep> is true,to_duration() returns d,
+otherwise to_duration() returns duration_cast<precision>(d)[.](#4.sentence-1)
+
+[🔗](#lib:is_negative,hh_mm_ss)
+
+`constexpr bool is_negative() const noexcept;
+`
+
+[5](#5)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8554)
+
+*Returns*: is_neg[.](#5.sentence-1)
+
+[🔗](#lib:hours,hh_mm_ss)
+
+`constexpr chrono::hours hours() const noexcept;
+`
+
+[6](#6)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8565)
+
+*Returns*: h[.](#6.sentence-1)
+
+[🔗](#lib:minutes,hh_mm_ss)
+
+`constexpr chrono::minutes minutes() const noexcept;
+`
+
+[7](#7)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8576)
+
+*Returns*: m[.](#7.sentence-1)
+
+[🔗](#lib:seconds,hh_mm_ss)
+
+`constexpr chrono::seconds seconds() const noexcept;
+`
+
+[8](#8)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8587)
+
+*Returns*: s[.](#8.sentence-1)
+
+[🔗](#lib:subseconds,hh_mm_ss)
+
+`constexpr precision subseconds() const noexcept;
+`
+
+[9](#9)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8598)
+
+*Returns*: ss[.](#9.sentence-1)
+
+[🔗](#lib:to_duration,hh_mm_ss)
+
+`constexpr precision to_duration() const noexcept;
+`
+
+[10](#10)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8609)
+
+*Returns*: If is_neg, returns -(h + m + s + ss),
+otherwise returns h + m + s + ss[.](#10.sentence-1)
+
+[🔗](#lib:operator_precision,hh_mm_ss)
+
+`constexpr explicit operator precision() const noexcept;
+`
+
+[11](#11)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8621)
+
+*Returns*: to_duration()[.](#11.sentence-1)

cppdraft/time/hms/nonmembers.md

@@ -0,0 +1,31 @@
+[time.hms.nonmembers]
+
+# 30 Time library [[time]](./#time)
+
+## 30.9 Class template hh_mm_ss [[time.hms]](time.hms#nonmembers)
+
+### 30.9.3 Non-members [time.hms.nonmembers]
+
+[🔗](#itemdecl:1)
+
+`template<class charT, class traits, class Duration>
+  basic_ostream<charT, traits>&
+    operator<<(basic_ostream<charT, traits>& os, const hh_mm_ss<Duration>& hms);
+`
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8635)
+
+*Effects*: Equivalent to:return os << format(os.getloc(), *STATICALLY-WIDEN*<charT>("{:L%T}"), hms);
+
+[2](#2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8642)
+
+[*Example [1](#example-1)*: for (auto ms : {-4083007ms, 4083007ms, 65745123ms}) { hh_mm_ss hms{ms};
+ cout << hms << '\n';} cout << hh_mm_ss{65745s} << '\n';
+
+Produces the output (assuming the "C" locale):-01:08:03.00701:08:03.00718:15:45.12318:15:45
+
+— *end example*]

cppdraft/time/hms/overview.md

@@ -0,0 +1,37 @@
+[time.hms.overview]
+
+# 30 Time library [[time]](./#time)
+
+## 30.9 Class template hh_mm_ss [[time.hms]](time.hms#overview)
+
+### 30.9.1 Overview [time.hms.overview]
+
+namespace std::chrono {template<class Duration> class hh_mm_ss {public:static constexpr unsigned fractional_width = *see below*; using precision = *see below*; constexpr hh_mm_ss() noexcept : hh_mm_ss{Duration::zero()} {}constexpr explicit hh_mm_ss(Duration d); constexpr bool is_negative() const noexcept; constexpr chrono::hours hours() const noexcept; constexpr chrono::minutes minutes() const noexcept; constexpr chrono::seconds seconds() const noexcept; constexpr precision subseconds() const noexcept; constexpr explicit operator precision() const noexcept; constexpr precision to_duration() const noexcept; private:bool is_neg; // *exposition only* chrono::hours h; // *exposition only* chrono::minutes m; // *exposition only* chrono::seconds s; // *exposition only* precision ss; // *exposition only*};}
+
+[1](#1)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8423)
+
+The hh_mm_ss class template
+splits a duration into a multi-field time structure*hours*:*minutes*:*seconds* and
+possibly *subseconds*,
+where *subseconds* will be a duration unit
+based on a non-positive power of 10[.](#1.sentence-1)
+
+The Duration template parameter dictates the precision
+to which the time is split[.](#1.sentence-2)
+
+A hh_mm_ss models negative durations
+with a distinct is_negative getter
+that returns true when the input duration is negative[.](#1.sentence-3)
+
+The individual duration fields always return non-negative durations
+even when is_negative() indicates
+the structure is representing a negative duration[.](#1.sentence-4)
+
+[2](#2)
+
+[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L8440)
+
+If Duration is not a specialization of duration,
+the program is ill-formed[.](#2.sentence-1)