From Jason Turner

[time.clock]

C++14 → C++17 3.6 KB 40 lines
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Archived: C++14 | C++17
Markdown: C++14 | C++17
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C++ Weekly: Ep 397

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  1. tmp/tmpso4up4gm/{from.md → to.md} +18 -16
tmp/tmpso4up4gm/{from.md → to.md} RENAMED
@@ -9,14 +9,14 @@ Objects of class `system_clock` represent wall clock time from the
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  system-wide realtime clock.
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  ``` cpp
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  class system_clock {
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  public:
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- typedef see below rep;
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- typedef ratio<unspecified, unspecified> period;
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- typedef chrono::duration<rep, period> duration;
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- typedef chrono::time_point<system_clock> time_point;
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  static constexpr bool is_steady = unspecified;
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  static time_point now() noexcept;
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  // Map to C API
@@ -24,33 +24,35 @@ public:
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  static time_point from_time_t(time_t t) noexcept;
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  };
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  ```
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  ``` cpp
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- typedef unspecified system_clock::rep;
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  ```
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  *Requires:*
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  `system_clock::duration::min() < system_clock::duration::zero()` shall
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- be `true`. This implies that `rep` is a signed type.
 
 
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  ``` cpp
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  static time_t to_time_t(const time_point& t) noexcept;
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  ```
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  *Returns:* A `time_t` object that represents the same point in time as
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  `t` when both values are restricted to the coarser of the precisions of
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- `time_t` and `time_point`. It is implementation defined whether values
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  are rounded or truncated to the required precision.
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  ``` cpp
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  static time_point from_time_t(time_t t) noexcept;
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  ```
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  *Returns:* A `time_point` object that represents the same point in time
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  as `t` when both values are restricted to the coarser of the precisions
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- of `time_t` and `time_point`. It is implementation defined whether
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  values are rounded or truncated to the required precision.
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  #### Class `steady_clock` <a id="time.clock.steady">[[time.clock.steady]]</a>
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  Objects of class `steady_clock` represent clocks for which values of
@@ -59,14 +61,14 @@ values of `time_point` advance at a steady rate relative to real time.
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  That is, the clock may not be adjusted.
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  ``` cpp
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  class steady_clock {
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  public:
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- typedef unspecified rep;
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- typedef ratio<unspecified, unspecified> period;
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- typedef chrono::duration<rep, period> duration;
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- typedef chrono::time_point<unspecified, duration> time_point;
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  static constexpr bool is_steady = true;
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  static time_point now() noexcept;
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  };
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  ```
@@ -78,14 +80,14 @@ shortest tick period. `high_resolution_clock` may be a synonym for
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  `system_clock` or `steady_clock`.
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  ``` cpp
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  class high_resolution_clock {
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  public:
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- typedef unspecified rep;
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- typedef ratio<unspecified, unspecified> period;
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- typedef chrono::duration<rep, period> duration;
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- typedef chrono::time_point<unspecified, duration> time_point;
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  static constexpr bool is_steady = unspecified;
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  static time_point now() noexcept;
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  };
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  ```
 
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  system-wide realtime clock.
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  ``` cpp
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  class system_clock {
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  public:
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+ using rep = see below;
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+ using period = ratio<unspecified, unspecified{}>;
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+ using duration = chrono::duration<rep, period>;
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+ using time_point = chrono::time_point<system_clock>;
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  static constexpr bool is_steady = unspecified;
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  static time_point now() noexcept;
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  // Map to C API
 
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  static time_point from_time_t(time_t t) noexcept;
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  };
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  ```
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  ``` cpp
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+ using system_clock::rep = unspecified;
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  ```
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  *Requires:*
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  `system_clock::duration::min() < system_clock::duration::zero()` shall
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+ be `true`.
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+
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+ [*Note 1*: This implies that `rep` is a signed type. — *end note*]
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  ``` cpp
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  static time_t to_time_t(const time_point& t) noexcept;
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  ```
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  *Returns:* A `time_t` object that represents the same point in time as
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  `t` when both values are restricted to the coarser of the precisions of
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+ `time_t` and `time_point`. It is *implementation-defined* whether values
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  are rounded or truncated to the required precision.
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  ``` cpp
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  static time_point from_time_t(time_t t) noexcept;
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  ```
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  *Returns:* A `time_point` object that represents the same point in time
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  as `t` when both values are restricted to the coarser of the precisions
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+ of `time_t` and `time_point`. It is *implementation-defined* whether
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  values are rounded or truncated to the required precision.
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  #### Class `steady_clock` <a id="time.clock.steady">[[time.clock.steady]]</a>
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  Objects of class `steady_clock` represent clocks for which values of
 
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  That is, the clock may not be adjusted.
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  ``` cpp
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  class steady_clock {
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  public:
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+ using rep = unspecified;
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+ using period = ratio<unspecified, unspecified{}>;
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+ using duration = chrono::duration<rep, period>;
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+ using time_point = chrono::time_point<unspecified, duration>;
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  static constexpr bool is_steady = true;
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  static time_point now() noexcept;
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  };
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  ```
 
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  `system_clock` or `steady_clock`.
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  ``` cpp
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  class high_resolution_clock {
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  public:
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+ using rep = unspecified;
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+ using period = ratio<unspecified, unspecified{}>;
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+ using duration = chrono::duration<rep, period>;
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+ using time_point = chrono::time_point<unspecified, duration>;
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  static constexpr bool is_steady = unspecified;
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  static time_point now() noexcept;
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  };
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  ```