kamicane/harmonizer

es6 transpiler

harmonizer's Issues

Using let renames wrong variables

let y = x => x * 2;
var z = x => ++x;

Compiles to

var yA = function (xA) {
  return xA * 2;
};
var z = function (x) {
  return ++xA;
};

The local variable x in function z shouldn't be renamed.

Support spread operator in destructing assigment

var [x, ...xs] = [1, 2, 3];

should yield in var x = 1 and var xs = [2, 3].

See also: https://bugzilla.mozilla.org/show_bug.cgi?id=933276

Unknown expression type: SpreadElement

given a source like

var ArrayLike = class extends Array {
  constructor(...args){
    if (args.length === 1 && typeof args[0] === 'Number') {
        this.length = args[0]
    }else{
        this.push.apply(this, args)
    }
  }
}

var HaskellArray = class extends ArrayLike {
  constructor(...args){
    if(args.length === 1) {
      super(0)
      this.push(args[0])
    }else{
      super(...args)
    }
  }
  head(){
    return new HaskellArray(this[0])
  }
  tail(){
    return new HaskellArray(...this.slice(1))
  }
}

I get an error while transpiling, trying the same code on http://kamicane.github.io/harmonizer-demo/
on the es5 output (escodegen) I can read the error Unknown expression type: SpreadElement on the tail method

Missing Type: ImportDeclaration

Guessing it's not supported as of yet, but for funzies here's the stack trace (Node v0.10.28):

node_modules/harmonizer/node_modules/nodes/lib/factory.js:475
  if (!NodeClass) throw new Error('missing type: ' + type);
                        ^
Error: missing type: ImportDeclaration
    at build (node_modules/nodes/lib/factory.js:475:25)
    at Array.map (native)
    at build (node_modules/harmonizer/node_modules/nodes/lib/factory.js:491:37)
    at transform (node_modules/harmonizer/index.js:56:17)