scripts should be wrapped in IIFEs on concatenation

[pwasem]

Scripts should each be wrapped in immediately invoked function expressions (IIFEs) on concatenation as mentioned in Effective Javascript by David Herman (chapter 1).
This would avoid several problems, e.g. considering scopes and usage of "use strict";

So instead of:

script_1;
script_2;
...
script_n;

The concatenated file should look like:

(function (){
  script_1
})();
(function (){
  script_2
})();
...
(function (){
  script_n
})();

Implementation should be easy:

var content = dom5.getTextContent(sn).trim();
// wrap content in immediately invoked function expression (IIFE)
let iifeContent = '(function(){\n' + content + '\n})();'
contents.push(iifeContent);

Thank you in advance!