Notes on converting CoffeeScript to ES6

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Some quick notes on hand-converting from CoffeeScript to ES6/ECMAScript 2015 (e.g. for use with bablejs):

• add 'use strict'; to beginning of file
• add let before new variable assignments, or const if they are constant
• add semicolons to end of statements (optional)
• add commas between elements of multi-line array literals
• add parenthesizes around function calls
• add braces around blocks
• replace (args) => with (args) => { arrow functions
• replace for x in a with for (let x of a) {
• replace # with // comments
• replace == with === and != with !== strict equality comparison
• replace "#{x}" with backquote template strings

`${x}`

• replace suffixed if/unless with prefixed if
• replace expression if x then y else z with ternary operator x ? y : z
• replace class Foo with class Foo {
• replace method declarations m: () -> with m() {
• replace class method declaration @m: () -> with static m() {
• replace class variable declaration @x = y with static property getter static get x() { return y; }
• replace @ instance variables with this.
• replace and with &&, or with ||, not with !
• replace x ? y existential operator with typeof(x) !== 'undefined' : x : y
• replace coffeeify browserify transform with babelify
• ...

note: these are simplified shortcuts, use with caution. references:

• http://coffeescript.org/#language
• https://babeljs.io/docs/learn-es6/