Crate tokio_js_set_interval

The crate tokio-js-set-interval allows you to use setInterval(callback, ms) and setTimeout(callback, ms) as in Javascript inside a tokio runtime (https://tokio.rs/). For this, it offers the macros set_interval!(callback, ms) and set_timeout!(callback, ms).

Restrictions

They behave similar to their Javascript counterparts, with a few exceptions:

• They only get executed if the tokio runtime lives long enough.
• on order to compile, the callback must return the union type, i.e. ()
• => all actions must be done via side effects
• ⚠ again, there is NO GUARANTEE that the tasks will get executed
  (–> but useful/convenient for low priority background tasks and for the learning effect of course) ⚠

Trivia

⚠ I’m not an expert in tokio (or async/await/futures in Rust in general) and I don’t know if this follows best practises. But it helped me to understand how tokio works. I hope it may be helpful to some of you too. ⚠

The functionality itself is really simple. The biggest part are the convenient macros. I over-engineered them a little to learn more about macros.

Compatibility

Version 1.0.0 is developed with:

• tokio @ 1.6.0 (but should also work with 1.0.0)
• rustc @ 1.52.1 (but should also work with 1.45.2)

Macros

set_interval	Creates a timeout that behaves similar to setInterval(callback, ms) in Javascript for the tokio runtime. Unlike in Javascript, it will only be executed, if after the specified time passed, the tokio runtime still lives, i.e. didn’t got dropped.
set_timeout	Creates a timeout that behaves similar to setTimeout(callback, ms) in Javascript for the tokio runtime. Unlike in Javascript, it will only be executed, if after the specified time passed, the tokio runtime still lives, i.e. didn’t got dropped.

Functions

_set_interval	INTERNAL Use macro set_interval instead!
_set_timeout	INTERNAL Use macro set_timeout instead!