Variable Grouping

Description

Variable Grouping groups your variable declarations into a single variable statement list. Additionally, variable hoisting is performed in optimization-time. Hoisting is JavaScript default behavior of moving declarations to the top of the scope. This behavior gives you the ability to declare a function or a variable after it is used.

Code Annotation Example

// @jscrambler enable variableGrouping

Examples

The following contrived example does nothing besides declaring a bunch of variables in different scopes:

var a = 1;
var b = 2;
(function () {
    var a = 1;
    var b = 2;
    var c = function () {
        var a = 1;
        var b = 2;
        var c = 3;
    }();
    var d = 2;
    function e() {}
    var f = 1;
    var g = 2;
}());
var f = 1;
var g = 2;

The resulting code looks like this:

var a, b, f, g;
a = 1;
b = 2;
(function () {
    var a, b, c, d, f, g;
    a = 1;
    b = 2;
    c = function () {
        var a, b, c;
        a = 1;
        b = 2;
        c = 3;
    }();
    d = 2;
    function e() {}
    f = 1;
    g = 2;
}());
f = 1;
g = 2;

Browser Compatibility

Browser	Compatible Versions	Tested Versions	Notes
Chrome	80+	80+
Firefox	90+	90+
Internet Explorer	8+	8+
Microsoft Edge	116+	116+
Safari	13.1+	13.1+

API Parameters

Example:

{
  "keys": {
    "accessKey": "XXXXXX",
    "secretKey": "YYYYYY"
  },
  "applicationId": "ZZZZZZ",
  "params": [
    {
      "name": "variableGrouping"
    }
  ]
}