# wasm-pack init

The `wasm-pack init` command creates the files neccessary for JavaScript
interoperability and for publishing a package to npm. This involves compiling
your code to wasm and generating a pkg folder. This pkg folder will contain the
wasm binary, a JS wrapper file, your `README`, and a `package.json` file.

## Path

The `wasm-pack init` command can be given an optional path argument, e.g.:

```
wasm-pack init examples/js-hello-world
```

This path should point to a directory that contains a `Cargo.toml` file. If no
path is given, the `init` command will run in the current directory.

## Target

The init command accepts a `--target` argument. This will customize the output files
to align with a particular type of JS module. This allows wasm-pack to generate either
ES6 modules or CommonJS modules for use in browser and in NodeJS. Defaults to `browser`.
The options are:

```
wasm-pack init --target nodejs
```

| Option    | Description                                                                                                     |
|-----------|-----------------------------------------------------------------------------------------------------------------|
| `nodejs`  | Outputs JS that uses CommonJS modules, for use with a `require` statement.                                      |
| `browser` | Outputs JS that uses ES6 modules, primarily for use with `import` statements and/or bundlers such as `webpack`. |

## Scope

The init command also accepts an optional `--scope` argument. This will scope
your package name, which is useful if your package name might conflict with
something in the public registry. For example:

```
wasm-pack init examples/js-hello-world --scope test
```

This command would create a `package.json` file for a package called
`@test/js-hello-world`. For more information about scoping, you can refer to
the npm documentation [here][npm-scope-documentation].

## Debug

The init command accepts an optional `--debug` argument. This will build the
output package using cargo's
[default non-release profile][cargo-profile-sections-documentation]. Building
this way is faster but applies few optimizations to the output, and enables
debug assertions and other runtime correctness checks.

The exact meaning of this flag may evolve as the platform matures.

[npm-scope-documentation]: https://docs.npmjs.com/misc/scope
[cargo-profile-sections-documentation]: https://doc.rust-lang.org/cargo/reference/manifest.html#the-profile-sections

## Skipping build

The init command accepts an optional `--skip-build` argument.

This will deactivate those steps:
- installing wasm target (via cargo)
- compiling the code to wasm
- installing wasm-bindgen (via rustup)
- running wasm-bindgen on the built wasm

Basically it will remains only the steps that update the metadata of `package.json`.