Dodgeball Cannon » Javascript

IE6 submit-click on text input submit

John Tantalo — Fri, 26 Sep 2008 23:15:44 +0000

Found this fun bug in IE6 today. If you have a text input and submit input unassociated with a form, then submitting the text input (by hitting return or enter when focused) will cause a click event on the submit input.

The solution is simple and intuitive: eliminate unassociated submit inputs and submit buttons.

Demo (IE only)

Custom Wikipedia CSS & Javascript for iPhone

John Tantalo — Sat, 02 Aug 2008 23:09:45 +0000

This afternoon I made a custom stylesheet and script to format Wikipedia nicely for me when I am logged on from my iPhone. If you have a Wikipedia account, you can easily use them by adding them to your own monobook.css and monobook.js. Screenshots below.

Dangers of anonymous function closures

John Tantalo — Mon, 07 Apr 2008 19:43:57 +0000

John Resig’s jQuery uses a standard technique of anonymous function closures to namespace its internal functionality.

(function(){
  // jQuery stuff goes here...
})();

This is all well and good until you want to inline this code under some of your application code, as I did while working on Eventful’s MySpace application. Consider this example, written in standard Javascript style.

var foo = function(bar) {
  console.log("foo");
  return bar;
}

(function(){
  console.log("bar")
})();

What do you expect this code to print? If you say “bar”, you’re wrong. It prints “foo bar” because in this context the anonymous function closure becomes a call to the function that prints “foo” and returns the function that prints “bar”, which is then called.

Most of us probably wouldn’t notice what just happened because we are so used to Javascript interpreters automatically inserting semicolons after function definitions.

The danger is assuming, as John Resig and hundreds others have, that your anonymous function closure is the first token in a new line. In my case, it wasn’t. The solution? Either start meticulously sprinkling semicolons in your application code, or just add a single semicolon before your parenthetical block, guaranteeing it’s the first token in the line.

;(function(){
  // jQuery stuff goes here...
})();