keysquash

An experimental JS "compression" pass that stores an index of long, frequently used key names

npm install keysquash
4 downloads in the last month

keysquash experimental

Keysquash is an experimental JS "compression" pass that stores an index of long, frequently used key names (e.g. addEventListener) and refers to that instead.

For example:

document.body.addEventListener('mousedown', function(e) {
  console.log('down', e.offsetX, e.offsetY)
})
document.body.addEventListener('mouseup', function(e) {
  console.log('up', e.offsetX, e.offsetY)
})

Would be transformed into this:

(function($__ks_) {
  document.body[$__ks_._]('mousedown', function(e) {
    console.log('down', e[$__ks_.$], e[$__ks_.a])
  })
  document.body[$__ks_._]('mousedown', function(e) {
    console.log('down', e[$__ks_.$], e[$__ks_.a])
  })
})({
    "_": "addEventListener"
  , "$": "offsetX"
  , "a": "offsetY"
})

Which can then get minified using uglifyjs -cm for further savings.

In practice it's a little smarter about making sure that replacing keys provides a file size improvement too, but make sure to double check this.

This is only worth using in special cases such as js13kgames. I'm not sure of all of the side-effects yet.

Installation

npm install -g keysquash

Usage

cat index.js | keysquash | uglifyjs -cm
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