rollup-plugin-purs
v1.0.38
Published
Bundle PureScript modules with Rollup
Downloads
206
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rollup-plugin-purs
Bundles PureScript modules with Rollup
Why Rollup?
Here are the file sizes for the examples/tab-organizer
program:
| Bundler | Unminified | JSMin | UglifyJS |
| ------------------ | ---------: | ---------: | ---------: |
| rollup-plugin-purs | 112.2 kB
| 70.3 kB
| 35.7 kB
|
| purs bundle | 157.8 kB
| 107.2 kB
| 65.2 kB
|
| webpack | 977.4 kB
| 654.0 kB
| 178.8 kB
|
Installation
Add the following to your
package.json
:"devDependencies": { "rollup": "^0.41.6", "rollup-plugin-purs": "^1.0.35" }, "scripts": { "build": "rollup --config" }
Run
npm install
Place this code into a file called
rollup.config.js
:import purs from "rollup-plugin-purs"; export default { entry: "src/Main.purs", dest: "bundle.js", format: "iife", sourceMap: true, plugins: [ purs() ] };
This plugin does not compile PureScript code, so you will need to run
pulp build -- --source-maps
(or equivalent)Run
npm run build
The final bundle is in the
bundle.js
file. Enjoy the smaller file size and optimizations!
You can see an example program in the examples/pulp init
folder.
Options
These are the default options:
purs({
include: undefined, // Glob pattern for files/directories to include
exclude: undefined, // Glob pattern for files/directories to exclude
buildDir: "output", // Directory where the `purs compile` files are located
runMain: true, // Whether to call the `main` function or not
debug: true, // Displays additional warnings and statistics
optimizations: {
uncurry: true, // Whether to apply the uncurrying optimization or not
inline: true, // Whether to inline some functions or not
removeDeadCode: true, // Whether to remove dead code or not
assumePureVars: true // Whether to assume that variable assignment is always pure
}
})
The default options should be fine for most use cases.
Optimizations
These are the optimizations which can be turned on or off:
uncurry
Replaces curried functions with uncurried functions, for improved performance and smaller file size.
inline
Inlines some functions, which can increase performance and decrease the file size.
It also inlines typeclass instance methods when it can. This can dramatically improve performance and reduce the file size.
removeDeadCode
Removes code which is not used. This dramatically reduces the file size.
assumePureVars
When there is a variable assignment like
var foo = ...
it will assume that the...
is pure. When used in combination withremoveDeadCode
, this significantly reduces the file size.If
assumePureVars
isfalse
, thenrollup-plugin-purs
only removes unused variables if it can prove that the variables are pure. But sometimes it won't remove unused variables, because it's not smart enough to realize that the variables are pure.If
assumePureVars
istrue
, thenrollup-plugin-purs
will remove all unused variables, even if it can't prove that the variables are pure.PureScript variables are always pure, so
assumePureVars
is safe. But if you do weird things with the FFI, or if you use an unsafe PureScript function, or if you import a JavaScript library, thenassumePureVars
might break your program.
In addition to the above optimizations, there are some optimizations which are always applied:
- Constant propagation / folding
Planned optimizations
- Common subexpression elimination
Comment pragmas
You can disable certain warnings by including a special comment in your code:
// rollup-plugin-purs ignore dynamic exports
// rollup-plugin-purs ignore dynamic require
// rollup-plugin-purs ignore dynamic module
Each comment disables a specific warning.
The comments must be exactly the same as above, and they must be placed at the top-level of your code, with zero spaces to the left of the comment.
Converting from CommonJS to ES6 modules
This package also contains a convert-commonjs
program which can be used to convert a file from CommonJS to ES6 modules.
You can run node_modules/.bin/convert-commonjs input.js > output.js
which will take the input.js
file (which is CommonJS) and will output to the output.js
file (which is ES6 modules).
License
MIT