6 releases

0.1.6 May 16, 2023
0.1.5 May 15, 2023
0.1.2 Feb 23, 2023

#351 in WebAssembly

MIT/Apache

16KB
244 lines

wasm_extra

Latest Version Downloads Documentation License Dependency Status

Extra utilities for WASM and web-sys.

Extension traits

The crate provides a number of extension traits for the web-sys types.

Macros

One of the things that this crate offers is the add_event_listener_with_callback! macro named after the ::web_sys::EventTarget::add_event_listener_with_callback() function.

The macro is a bit more ergonomic to use and code with it is easier to mentally parse than the corresponding code without it.

side-by-side comparison of the macro and the function

In the expanded code, the event target (open_files_btn) appears only on line 16, whereas in the macro it's the very first argument, which then followed by the event name, then the "closure prologue", and - lastly - the closure itself.

"Closure prologue" is a stipulative term for the code that is executed before the closure itself. It's useful for preparing the closure's environment, for example, by cloning the variables before capturing.

In the code above it's empty but in the following example it's not:

example of the closure prologue

In addition, in the code above the event target is captured by the closure. This requires special handling and is done with the ampersand before the event target's variable.

SemVer Policy

At the moment, there's no any semver guarantees. The crate is being inactively developed.

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this crate by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

Dependencies

~6.5–9MB
~171K SLoC