peterd (6) [Avatar] Offline
JSHint is reporting some errors/warnings in Listing 2.3 (mainly missing ";" after `script.src = url`) and missing `{` and `}` from the `if (script.addEventListener)` statement.

Oddly, I'm not seeing a warning for the fishy `attachEvent('onreadystatechange', readyHandler = function () {` line. I thought JSHint would complain that readyHandler was not previously defined using var/function. May be worth asking Anton why that isn't an error/warning from JSHint, actually.

Tweaked source below:

function loadScript(url, callback) {
var script = document.createElement('script');
script.type = 'text/javascript';
script.async = true;
script.src = url;

var entry = document.getElementsByTagName('script')[0];
entry.parentNode.insertBefore(script, entry);

if (script.addEventListener) {
script.addEventListener('load', callback, false);
} else {
script.attachEvent('onreadystatechange', readyHandler = function () {
if (/complete|loaded/.test(script.readyState)) {
script.detachEvent('onreadystatechange', readyHandler);
benvinegar (68) [Avatar] Offline
Re: Listing 2.3 vs JSHint
Okay, good catch. I think I'll change that function definition to not use the fn = name syntax anyways.

Out of curiosity, are you just copy/pasting these into the JSHint website?
peterd (6) [Avatar] Offline
Re: Listing 2.3 vs JSHint
Yeah, I'm just manually copy/pasting in to the JSHint website to quickly check if the code validates. There were a couple other examples which were missing the odd semicolon which I didn't bother noting. If you want I can post those comments too, but if it doesn't look like I/we have access to the latest book source it may not be worth me filing issues for this stuff.