wasm-pack/docs/setup.md

Setup

Installing wasm-pack

You can install wasm-pack using the following command:

cargo install wasm-pack

If you have already installed wasm-pack and want to install a newer version, you can use the --force option, like this:

cargo install wasm-pack --force

Project Initialization

You can create a new Rust project named my-lib using this command.

cargo new --lib my-lib

The --lib flag specifies that the project is a library, which is important because we will be calling this code from JavaScript.

Cargo.toml changes

You will need to add wasm-bindgen to your Cargo.toml in the dependencies section. wasm-bindgen is a tool that facilitates interoperability between wasm modules and JavaScript.

Next, add a [lib] section, with a new field named crate-type set to "cdylib". This specifies that the library is a C compatible dynamic library, which helps cargo pass the correct flags to the Rust compiler when targeting wasm32.

After making these changes, your Cargo.toml file should look something like this:

[package]
name = "wasm-add"
version = "0.1.0"
authors = ["Michael Gattozzi <mgattozzi@gmail.com>"]
description = "Code used to demonstrate how to use wasm-pack"
license = "MIT/Apache-2.0"
repository = "https://github.com/mgattozzi/wasm-add"

[lib]
crate-type = ["cdylib"]

[dependencies]
wasm-bindgen="0.2"