commit | a18edb3289aec2ac3b8adcc24ddf8c70b717a0bc | [log] [tgz] |
---|---|---|
author | Xin Li <[email protected]> | Sat Feb 20 12:06:21 2021 +0000 |
committer | Automerger Merge Worker <[email protected]> | Sat Feb 20 12:06:21 2021 +0000 |
tree | cca5bb2f710f5667d61900a53bea9e4dacef32a3 | |
parent | 4920b2a264d51fd44c88acd474baba920e91cb96 [diff] | |
parent | 1afc95659991d2fbf86c26f9e98209d4247ac1b9 [diff] |
[automerger skipped] Mark ab/7061308 as merged in stage. am: 04bd053b28 -s ours am: 1afc956599 -s ours am skip reason: Change-Id Id5737bba7df51ee3c84c339917f59b00d9f283f6 with SHA-1 7b1b61840e is in history Original change: undetermined MUST ONLY BE SUBMITTED BY AUTOMERGER Change-Id: I65ca90f59459f0651bbff4f609852cecb2008716
If you call std::time::Instant::now()
on a WASM platform, it will panic. This crate provides a partial replacement for std::time::Instant
that works on WASM too. This defines the type instant::Instant
which is:
wasm32-unknown-unknown
or wasm32-unknown-asmjs
and you enabled either the stdweb
or the wasm-bindgen
feature. This emulation is based on the javascript performance.now()
function.std::time::Instant
otherwise.Note that even if the stdweb or wasm-bindgen feature is enabled, this crate will continue to rely on std::time::Instant
as long as you are not targeting wasm32. This allows for portable code that will work on both native and WASM platforms.
now
.By enabling the feature now
the function instant::now()
will be exported and will either:
performance.now()
when compiling for a WASM platform with the features stdweb or wasm-bindgen enabled, or using a custom javascript function.time::precise_time_s() * 1000.0
otherwise.The result is expressed in milliseconds.
instant
for a native platform.Cargo.toml:
[dependencies] instant = "0.1"
main.rs:
fn main() { // Will be the same as `std::time::Instant`. let now = instant::Instant::new(); }
instant
for a WASM platform.This example shows the use of the stdweb
feature. It would be similar with wasm-bindgen
.
Cargo.toml:
[dependencies] instant = { version = "0.1", features = [ "stdweb" ] }
main.rs:
fn main() { // Will emulate `std::time::Instant` based on `performance.now()`. let now = instant::Instant::new(); }
instant
for a WASM platform where performance.now()
is not available.This example shows the use of the inaccurate
feature.
Cargo.toml:
[dependencies] instant = { version = "0.1", features = [ "wasm-bindgen", "inaccurate" ] }
main.rs:
fn main() { // Will emulate `std::time::Instant` based on `Date.now()`. let now = instant::Instant::new(); }
instant
for any platform enabling a feature transitively.Cargo.toml:
[features] stdweb = [ "instant/stdweb" ] wasm-bindgen = [ "instant/wasm-bindgen" ] [dependencies] instant = "0.1"
lib.rs:
fn my_function() { // Will select the proper implementation depending on the // feature selected by the user. let now = instant::Instant::new(); }
now
.Cargo.toml:
[features] stdweb = [ "instant/stdweb" ] wasm-bindgen = [ "instant/wasm-bindgen" ] [dependencies] instant = { version = "0.1", features = [ "now" ] }
lib.rs:
fn my_function() { // Will select the proper implementation depending on the // feature selected by the user. let now_instant = instant::Instant::new(); let now_milliseconds = instant::now(); // In milliseconds. }
now
without stdweb
or wasm-bindgen
.Cargo.toml:
[dependencies] instant = { version = "0.", features = [ "now" ] }
lib.rs:
fn my_function() { // Will use the 'now' javascript implementation. let now_instant = instant::Instant::new(); let now_milliseconds = instant::now(); // In milliseconds. }
javascript WASM bindings file:
function now() { return Date.now() / 1000.0; }