Crate javy

Configurable JavaScript runtime for WebAssembly.

Example usage:

use anyhow::anyhow;
use javy::{Runtime, from_js_error};
let runtime = Runtime::default();
let context = runtime.context();

context.with(|cx| {
    let globals = this.globals();
    globals.set(
        "print_hello",
        Function::new(
            this.clone(),
            MutFn::new(move |_, _| {
                println!("Hello, world!");
            }),
        )?,
    )?;
});

context.with(|cx| {
    cx.eval_with_options(Default::default(), "print_hello();")
        .map_err(|e| from_js_error(cx.clone(), e))
        .map(|_| ())
});

Core concepts

• Runtime - The entrypoint for using the JavaScript runtime. Use a Config to configure behavior.

Features

• export_alloc_fns - exports alloc::canonical_abi_realloc and alloc::canonical_abi_free from generated WebAssembly for allocating and freeing memory
• json - functions for converting between [quickjs::JSValueRef] and JSON byte slices
• messagepack - functions for converting between [quickjs::JSValueRef] and MessagePack byte slices

Re-exports

• pub use rquickjs as quickjs;

Modules

• alloc

Macros

• hold
  Alias for Args::hold
• hold_and_release
  Alias for [Args::hold(cx, args).release()]

Structs

• Args
  A struct to hold the current Ctx and Values passed as arguments to Rust functions. A struct here is used to explicitly tie these values with a particular lifetime.
• Config
  A configuration for Runtime.
• Runtime
  A JavaScript Runtime.

Functions

• from_js_error
  Handles a JavaScript error or exception and converts to anyhow::Error.
• to_js_error
  Converts an anyhow::Error to a JSError.
• to_string_lossy
  Converts the JavaScript value to a string, replacing any invalid UTF-8 sequences with the Unicode replacement character (U+FFFD).
• val_to_string
  Retrieves the string representation of a JavaScript value.