# purs-loader
-> [PureScript](http://www.purescript.org) loader for [webpack](https://github.com/webpack/webpack)
+> [PureScript](http://www.purescript.org) loader for [webpack](http://webpack.github.io)
+
+- Supports hot-reloading and rebuilding of single source files
+- Dead code elimination using the `bundle` option
+- Colorized build output using `purescript-psa` and the `psc: "psa"` option
## Install
-Install with [npm](https://npmjs.org/package/purs-loader)
+Install with [npm](https://npmjs.org/package/purs-loader).
```
+// For PureScript 0.11 and newer
npm install purs-loader --save-dev
-```
-## Options
-
-#### options
-
- - **no-prelude**: Boolean value that toggles `--no-prelude`
- - Do not include the Prelude in the generated Javascript.
- - **no-opts**: Boolean value that toggles `--no-opts`
- - Disable all optimizations.
- - **no-magic-do**: Boolean value that toggles `--no-magic-do`
- - Turn off optimizations which inline calls to >>= for the Eff monad.
- - **no-tco**: Boolean value that toggles `--no-tco`
- - Turn off tail-call elimination.
- - **runtime-type-checks**: Boolean value that toggles `--runtime-type-checks`
- - Generate simple runtime type checks for function arguments with simple types.
- - **verbose-errors**: Boolean value that toggles `--verbose-errors`
- - Generate verbose error messages.
- - **output**: String value that sets `--output=<string>`
- - Write the generated Javascript to the specified file.
+// For PureScript 0.9 and 0.10
+npm install purs-loader@purescript-0.9 --save-dev
+
+// For PureScript 0.8
+npm install purs-loader@purescript-0.8 --save-dev
+```
## Example
-```js
-var path = require('path');
-
-module.exports = {
- entry: './src/test',
- output: {
- path: path.join(__dirname, 'dist'),
- filename: 'app.js'
- },
- module: {
- loaders: [{
+```javascript
+const webpackConfig = {
+ // ...
+ loaders: [
+ // ...
+ {
test: /\.purs$/,
- loader: 'purs-loader?no-prelude&output=output'
- }]
- },
- resolve: {
- modulesDirectories: [
- 'node_modules',
- 'web_modules',
- 'output'
- ]
- }
-};
+ loader: 'purs-loader',
+ exclude: /node_modules/,
+ query: {
+ psc: 'psa',
+ src: ['bower_components/purescript-*/src/**/*.purs', 'src/**/*.purs']
+ }
+ }
+ // ...
+ ]
+ // ...
+}
+```
+
+Refer to the [purescript-webpack-example](https://github.com/ethul/purescript-webpack-example) for a more detailed example.
+
+### Options
+
+Default options:
+
+```javascript
+const loaderConfig = {
+ psc: 'psc',
+ pscArgs: {},
+ pscBundle: 'psc-bundle',
+ pscBundleArgs: {},
+ pscIde: false, // instant rebuilds using psc-ide-server (experimental)
+ pscIdeArgs: {}, // for example, to use different psc-ide-server port: {port: 4088}
+ pscIdeServerArgs: {}, // for example, to change the port { port: 4088 }
+ pscIdeColors: false, // defaults to true if psc === 'psa'
+ pscPackage: false,
+ bundleOutput: 'output/bundle.js',
+ bundleNamespace: 'PS',
+ bundle: false,
+ warnings: true,
+ watch: false, // indicates if webpack is in watch mode
+ output: 'output',
+ src: [
+ path.join('src', '**', '*.purs'),
+ // if pscPackage = false
+ path.join('bower_components', 'purescript-*', 'src', '**', '*.purs')
+ // if pscPackage = true
+ // source paths reported by `psc-package sources`
+ ]
+}
```
+
+### `psc-ide` support (experimental)
+
+Experimental support for instant rebuilds using `psc-ide-server` can be enabled
+via the `pscIde: true` option.
+You can use an already running `psc-ide-server` instance by specifying the port in `pscIdeArgs`,
+if there is no server running this loader will start one for you.
+
+### `psc-package` support (experimental)
+
+Set `pscPackage` query parameter to `true` to enable `psc-package` support. The `psc-package`-supplied source paths
+will be appended to `src` parameter.
+
+### Troubleshooting
+
+#### Slower webpack startup after enabling psc-ide support?
+
+By default, the psc-ide-server will be passed the globs from query.src, this is
+helpful for other tools using psc-ide-server (for example IDE plugins), however
+it might result in a slower initial webpack startup time (rebuilds are not
+affected). To override the default behaviour, add:
+`pscIdeServerArgs: { "_": ['your/*globs/here'] }` to the loader config
+
+#### Errors not being displayed in watch mode?
+
+When the `watch` option is set to `true`, psc errors are appended to
+webpack's compilation instance errors array and not passed back as an
+error to the loader's callback. This may result in the error not being
+reported by webpack. To display errors, the following plugin may be added
+to the webpack config.
+
+```javascript
+const webpackConfig = {
+ // ...
+ plugins: [
+ function(){
+ this.plugin('done', function(stats){
+ process.stderr.write(stats.toString('errors-only'));
+ });
+ }
+ ]
+ // ...
+}
+```
+
+#### Error `spawn ENOENT`
+
+This is caused when the loader tries to spawn a binary that does not exists
+(`file or directory not found`). If you call webpack like `webpack` or
+`webpack --watch`, then ensure that all required binaries that the
+loader depends on are available in your `$PATH`.
+
+If you run webpack through an npm script (e.g., npm run or npm start) on NixOS,
+then it will first attempt to find binaries in `node_packages/.bin`.
+If you have the compiler installed through `npm` and it finds it there, this will
+cause `ENOENT`on Nix, because [the binary needs to be patched first, but npm will
+install the binary that is linked with /lib64/ld-linux-x86-64.so.2 - a file that
+will not exist at that path in NixOS](https://github.com/ethul/purescript-webpack-example/issues/5#issuecomment-282492131).
+The solution is to simply use the compiler from `haskellPackages.purescript` and
+make sure that it's available in `$PATH`. For more information about how to make
+it work on Nix, see [Purescript Webpack Example](https://github.com/ethul/purescript-webpack-example#using-globally-installed-binaries)