12 ms·I think minifiers use the former because it's shorter, and thus requires less space.by ekmartin 12y agoI think minifiers use the former because it's shorter, and thus requires less space.phpnode 12y agothe other benefit is that `void 0` cannot be overwritten in sloppy mode, whereas you can do something crazy like this: undefined = 'lol';evilpie 12y agoNo you can't. You can do something like function(undefined) {}, but the global 'undefined' is non-writable and non-configurable.ahoge 12y agoThat's an ES5 change. With ES3, you can overwrite NaN, Infinity, and undefined.LunaSea 12y agoOnly in strict mode I though no ?ahoge 12y agoGenerally. Technically, it's a "breaking change". As you can imagine, this didn't actually affect anyone.