diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/std/monotimes.nim | 86 |
1 files changed, 44 insertions, 42 deletions
diff --git a/lib/std/monotimes.nim b/lib/std/monotimes.nim index f84670ecc..78736d719 100644 --- a/lib/std/monotimes.nim +++ b/lib/std/monotimes.nim @@ -8,34 +8,38 @@ # ##[ - The ``std/monotimes`` module implements monotonic timestamps. A monotonic - timestamp represents the time that has passed since some system defined - point in time. The monotonic timestamps are guaranteed to always increase, - meaning that that the following is guaranteed to work: - - .. code-block:: nim - let a = getMonoTime() - # ... do some work - let b = getMonoTime() - assert a <= b - - This is not guaranteed for the `times.Time` type! This means that the - `MonoTime` should be used when measuring durations of time with - high precision. - - However, since `MonoTime` represents the time that has passed since some - unknown time origin, it cannot be converted to a human readable timestamp. - If this is required, the `times.Time` type should be used instead. - - The `MonoTime` type stores the timestamp in nanosecond resolution, but note - that the actual supported time resolution differs for different systems. - - See also - ======== - * `times module <times.html>`_ +The `std/monotimes` module implements monotonic timestamps. A monotonic +timestamp represents the time that has passed since some system defined +point in time. The monotonic timestamps are guaranteed to always increase, +meaning that that the following is guaranteed to work: ]## -import times +runnableExamples: + import std/os + + let a = getMonoTime() + sleep(10) + let b = getMonoTime() + assert a < b + +##[ +This is not guaranteed for the `times.Time` type! This means that the +`MonoTime` should be used when measuring durations of time with +high precision. + +However, since `MonoTime` represents the time that has passed since some +unknown time origin, it cannot be converted to a human readable timestamp. +If this is required, the `times.Time` type should be used instead. + +The `MonoTime` type stores the timestamp in nanosecond resolution, but note +that the actual supported time resolution differs for different systems. + +See also +======== +* `times module <times.html>`_ +]## + +import std/times type MonoTime* = object ## Represents a monotonic timestamp. @@ -53,18 +57,16 @@ when defined(macosx): when defined(js): proc getJsTicks: float = - ## Returns ticks in the unit seconds - {.emit: """ - var isNode = typeof module !== 'undefined' && module.exports - - if (isNode) { - var process = require('process'); - var time = process.hrtime() - return time[0] + time[1] / 1000000000; - } else { - return window.performance.now() / 1000; - } - """.} + ## Returns ticks in the unit seconds. + when defined(nodejs): + {.emit: """ + let process = require('process'); + let time = process.hrtime(); + `result` = time[0] + time[1] / 1000000000; + """.} + else: + proc jsNow(): float {.importjs: "window.performance.now()".} + result = jsNow() / 1000 # Workaround for #6752. {.push overflowChecks: off.} @@ -75,7 +77,7 @@ when defined(js): {.pop.} elif defined(posix) and not defined(osx): - import posix + import std/posix elif defined(windows): proc QueryPerformanceCounter(res: var uint64) {. @@ -84,11 +86,11 @@ elif defined(windows): importc: "QueryPerformanceFrequency", stdcall, dynlib: "kernel32".} proc getMonoTime*(): MonoTime {.tags: [TimeEffect].} = - ## Get the current `MonoTime` timestamp. + ## Returns the current `MonoTime` timestamp. ## ## When compiled with the JS backend and executed in a browser, - ## this proc calls `window.performance.now()`, which is not supported by - ## older browsers. See [MDN](https://developer.mozilla.org/en-US/docs/Web/API/Performance/now) + ## this proc calls `window.performance.now()`. + ## See [MDN](https://developer.mozilla.org/en-US/docs/Web/API/Performance/now) ## for more information. when defined(js): let ticks = getJsTicks() |