Imports

<h1><a id="imports"></a>World imports</h1> <ul> <li>Imports: <ul> <li>interface <a href="#wasi_clocks_types_0_3_1"><code>wasi:clocks/[email protected]</code></a></li> <li>interface <a href="#wasi_clocks_monotonic_clock_0_3_1"><code>wasi:clocks/[email protected]</code></a></li> <li>interface <a href="#wasi_clocks_system_clock_0_3_1"><code>wasi:clocks/[email protected]</code></a></li> <li>interface <a href="#wasi_clocks_timezone_0_3_1"><code>wasi:clocks/[email protected]</code></a></li> </ul> </li> </ul> <h2><a id="wasi_clocks_types_0_3_1"></a>Import interface wasi:clocks/[email protected]</h2> <p>This interface common types used throughout wasi:clocks.</p> <hr /> <h3>Types</h3> <h4><a id="duration"></a><code>type duration</code></h4> <p><code>u64</code></p> <p>A duration of time, in nanoseconds. <h2><a id="wasi_clocks_monotonic_clock_0_3_1"></a>Import interface wasi:clocks/[email protected]</h2> <p>WASI Monotonic Clock is a clock API intended to let users measure elapsed time.</p> <p>It is intended to be portable at least between Unix-family platforms and Windows.</p> <p>A monotonic clock is a clock which has an unspecified initial value, and successive reads of the clock will produce non-decreasing values.</p> <hr /> <h3>Types</h3> <h4><a id="duration"></a><code>type duration</code></h4> <p><a href="#duration"><a href="#duration"><code>duration</code></a></a></p> <p> <h4><a id="mark"></a><code>type mark</code></h4> <p><code>u64</code></p> <p>A mark on a monotonic clock is a number of nanoseconds since an unspecified initial value, and can only be compared to instances from the same monotonic-clock. <hr /> <h3>Functions</h3> <h4><a id="now"></a><code>now: func</code></h4> <p>Read the current value of the clock.</p> <p>The clock is monotonic, therefore calling this function repeatedly will produce a sequence of non-decreasing values.</p> <p>For completeness, this function traps if it's not possible to represent the value of the clock in a <a href="#mark"><code>mark</code></a>. Consequently, implementations should ensure that the starting time is low enough to avoid the possibility of overflow in practice.</p> <h5>Return values</h5> <ul> <li><a id="now.0"></a> <a href="#mark"><a href="#mark"><code>mark</code></a></a></li> </ul> <h4><a id="get_resolution"></a><code>get-resolution: func</code></h4> <p>Query the resolution of the clock. Returns the duration of time corresponding to a clock tick.</p> <h5>Return values</h5> <ul> <li><a id="get_resolution.0"></a> <a href="#duration"><a href="#duration"><code>duration</code></a></a></li> </ul> <h4><a id="wait_until"></a><code>wait-until: func</code></h4> <p>Wait until the specified mark has occurred.</p> <h5>Params</h5> <ul> <li><a id="wait_until.when"></a><code>when</code>: <a href="#mark"><a href="#mark"><code>mark</code></a></a></li> </ul> <h4><a id="wait_for"></a><code>wait-for: func</code></h4> <p>Wait for the specified duration to elapse.</p> <h5>Params</h5> <ul> <li><a id="wait_for.how_long"></a><code>how-long</code>: <a href="#duration"><a href="#duration"><code>duration</code></a></a></li> </ul> <h2><a id="wasi_clocks_system_clock_0_3_1"></a>Import interface wasi:clocks/[email protected]</h2> <p>WASI System Clock is a clock API intended to let users query the current time. The clock is not necessarily monotonic as it may be reset.</p> <p>It is intended to be portable at least between Unix-family platforms and Windows.</p> <p>External references may be reset, so this clock is not necessarily monotonic, making it unsuitable for measuring elapsed time.</p> <p>It is intended for reporting the current date and time for humans.</p> <hr /> <h3>Types</h3> <h4><a id="duration"></a><code>type duration</code></h4> <p><a href="#duration"><a href="#duration"><code>duration</code></a></a></p> <p> <h4><a id="instant"></a><code>record instant</code></h4> <p>An &quot;instant&quot;, or &quot;exact time&quot;, is a point in time without regard to any time zone: just the time since a particular external reference point, often called an &quot;epoch&quot;.</p> <p>Here, the epoch is 1970-01-01T00:00:00Z, also known as <a href="https://pubs.opengroup.org/onlinepubs/9699919799/xrat/V4_xbd_chap04.html#tag_21_04_16">POSIX's Seconds Since the Epoch</a>, also known as <a href="https://en.wikipedia.org/wiki/Unix_time">Unix Time</a>.</p> <p>Note that even if the seconds field is negative, incrementing nanoseconds always represents moving forwards in time. For example, <code>{ -1 seconds, 999999999 nanoseconds }</code> represents the instant one nanosecond before the epoch. For more on various different ways to represent time, see https://tc39.es/proposal-temporal/docs/timezone.html</p> <h5>Record Fields</h5> <ul> <li><a id="instant.seconds"></a><code>seconds</code>: <code>s64</code></li> <li><a id="instant.nanoseconds"></a><code>nanoseconds</code>: <code>u32</code></li> </ul> <hr /> <h3>Functions</h3> <h4><a id="now"></a><code>now: func</code></h4> <p>Read the current value of the clock.</p> <p>This clock is not monotonic, therefore calling this function repeatedly will not necessarily produce a sequence of non-decreasing values.</p> <p>The nanoseconds field of the output is always less than 1000000000.</p> <h5>Return values</h5> <ul> <li><a id="now.0"></a> <a href="#instant"><a href="#instant"><code>instant</code></a></a></li> </ul> <h4><a id="get_resolution"></a><code>get-resolution: func</code></h4> <p>Query the resolution of the clock. Returns the smallest duration of time that the implementation permits distinguishing.</p> <h5>Return values</h5> <ul> <li><a id="get_resolution.0"></a> <a href="#duration"><a href="#duration"><code>duration</code></a></a></li> </ul> <h2><a id="wasi_clocks_timezone_0_3_1"></a>Import interface wasi:clocks/[email protected]</h2> <hr /> <h3>Types</h3> <h4><a id="instant"></a><code>type instant</code></h4> <p><a href="#instant"><a href="#instant"><code>instant</code></a></a></p> <p> <hr /> <h3>Functions</h3> <h4><a id="iana_id"></a><code>iana-id: func</code></h4> <p>Return the IANA identifier of the currently configured timezone. This should be an identifier from the IANA Time Zone Database.</p> <p>For displaying to a user, the identifier should be converted into a localized name by means of an internationalization API.</p> <p>If the implementation does not expose an actual timezone, or is unable to provide mappings from times to deltas between the configured timezone and UTC, or determining the current timezone fails, or the timezone does not have an IANA identifier, this returns nothing.</p> <h5>Return values</h5> <ul> <li><a id="iana_id.0"></a> option&lt;<code>string</code>&gt;</li> </ul> <h4><a id="utc_offset"></a><code>utc-offset: func</code></h4> <p>The number of nanoseconds difference between UTC time and the local time of the currently configured timezone, at the exact time of <a href="#instant"><code>instant</code></a>.</p> <p>The magnitude of the returned value will always be less than 86,400,000,000,000 which is the number of nanoseconds in a day (24<em>60</em>60*1e9).</p> <p>If the implementation does not expose an actual timezone, or is unable to provide mappings from times to deltas between the configured timezone and UTC, or determining the current timezone fails, this returns nothing.</p> <h5>Params</h5> <ul> <li><a id="utc_offset.when"></a><code>when</code>: <a href="#instant"><a href="#instant"><code>instant</code></a></a></li> </ul> <h5>Return values</h5> <ul> <li><a id="utc_offset.0"></a> option&lt;<code>s64</code>&gt;</li> </ul> <h4><a id="to_debug_string"></a><code>to-debug-string: func</code></h4> <p>Returns a string that is suitable to assist humans in debugging whether any timezone is available, and if so, which. This may be the same string as <a href="#iana_id"><code>iana-id</code></a>, or a formatted representation of the UTC offset such as <code>-04:00</code>, or something else.</p> <p>WARNING: The returned string should not be consumed mechanically! It may change across platforms, hosts, or other implementation details. Parsing this string is a major platform-compatibility hazard.</p> <h5>Return values</h5> <ul> <li><a id="to_debug_string.0"></a> <code>string</code></li> </ul>