Jogs

Quickjs javascript runtime for typst. This package provides a typst plugin for evaluating javascript code.

Example

#import "@preview/jogs:0.2.3": *

#set page(height: auto, width: auto, fill: black, margin: 1em)
#set text(fill: white)

#let code = ```
function sum() {
  const total = Array.prototype.slice.call(arguments).reduce(function(a, b) {
      return a + b;
  }, 0);
  return total;
}

function string_join(arr) {
  return arr.join(" | ");
}

function return_complex_obj() {
  return {
    a: 1,
    b: "2",
    c: [1, 2, 3],
    d: {
      e: 1,
    },
  };
}

let bytecode = compile-js(code)

list-global-property(bytecode)

call-js-function(bytecode, "sum", 6, 7, 8, 9, 10)

call-js-function(bytecode, "string_join", ("a", "b", "c", "d", "e"),)

call-js-function(bytecode, "return_complex_obj",)

result: 

![](typst-package/examples/fib.svg)

## Documentation

This package provide following function(s):

### `eval-js`

Run a Javascript code snippet.

#### Arguments
* `code` - The Javascript code to run. It can be a string or a raw block.

#### Returns
The result of the Javascript code. The type is the typst type which most closely resembles the Javascript type.

#### Example

```typ
#let result = eval-js("1 + 1")

compile-js

Compile a Javascript code snippet into bytecode.

Arguments

• code - The Javascript code to compile. It can be a string or a raw block.

Returns

The bytecode of the Javascript code. The type is bytes.

Example

#let bytecode = compile-js("function sum(a, b) { return a + b; }")

call-js-function

Call a Javascript function with arguments.

Arguments

• bytecode - The bytecode of the Javascript function. It can be obtained by calling compile-js.
• name - The name of the Javascript function.
• ..args - The arguments to pass to the Javascript function. All other positional arguments are passed to the Javascript function as is.

Returns

The result of the Javascript function. The type is the typst type which most closely resembles the Javascript type.

Example

#let bytecode = compile-js("function sum(a, b) { return a + b; }")
#let result = call-js-function(bytecode, "sum", 1, 2)

list-global-property

List all global properties of a compiled Javascript bytecode. This is useful for inspecting the compiled Javascript bytecode.

Arguments

• bytecode - The bytecode of the Javascript function. It can be obtained by calling compile-js.

Returns

A list of all global properties of the Javascript bytecode. The type is array.

Example

#let bytecode = compile-js("function sum(a, b) { return a + b; }")
#let result = list-global-property(bytecode)

Build From Source

To build this project from source, you would need the following tools:

1. wasm-pack
2. wasi-stub from wasm-minimal-protocol
3. cargo-about Once you've installed them, you can run install.sh script to build plugin.

Installing the wasi-stub tool might be confusing for those who aren't familiar with typst or rust toolchain. Here's the detail instruction on how to build it from source.

1. Clone the wasm-minimal-protocol repo to your own computer, normally we just need the latest version of it, not the full history.

   git clone https://github.com/astrale-sharp/wasm-minimal-protocol/ --depth=1

2. Enter the repo's sub-directory called wasi-stub, and build the tool using cargo.

   cd wasm-minimal-protocol/wasi-stub
   cargo build
   # Better copy one to the project's root directory, so the build.sh script would detect it in build process.
   cp ../target/debug/wasi-stub ../.. 

3. (Optional) Safely delete the wasm-minimal-protocol repo, we wouldn't made any changes to it.