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Apple Mail can't count

I never noticed that before… I wonder what the cutoff is…

Note: I like Apple Mail, this is not a complaint!

I’ve been working on a CMS lately and having to create thumbnails for uploaded images is always a pain, lots of maths working out the correct sizes and such, so I’ve created a fairly small script to manipulate images in an object-oriented style.

For example:

scale(400, 300);
$image->write('small-image.jpg');
 
$image2 = new Image('image2.jpg');
$image2->watermark = 'sample.png';
$image2->output();

I’ve only implemented a few of the GD library methods, but I think these are the most useful methods. I might have to work on something that rounds the corners too, but I don’t have any need for it just yet.

There’s a demo page as ever, and you can get the script here (It’s a bit big, because the sample image is included, here’s one without it).

I stumbled across something odd today in PHP:

$r = '';
$r .= $r .= $r .= 'a';

Now, personally, I’d have expected a syntax error from the above code, but the result was even more confusing at first…

print $r; // 'aaaa'

Not sure if this was the expected output or not I tested similar code in other languages:

Ruby:

r = ''
r += r += r += 'a'
puts r # 'a'

Python:

r = ''
r += r += r += 'a'
#   File "", line 1
#     r += r += r += 'a'
#             ^
# SyntaxError: invalid syntax

Javascript:

var r = '';
r += r += r += 'a';
alert(r); // 'a'

Perl:

my $r = '';
$r .= $r .= $r .= 'a';
print $r; // 'aaaa'

That explains it!

So the reason the string is ‘aaaa’ seems to be that the code is evaluated from right to left:

$r = '';
$r += $r += $r += 'a';
 
// How it works:
//
// $r += 'a'; // 'a'
// $r += $r += 'a'; // 'a' + 'a';
// $r += $r += $r += 'a'; // 'aa' + ('a' + 'a')

I don’t think it’s a bug, well, at least I assume not, but is there a name for this?

Update: I asked some clever people for help understanding it.

Probably not the first person to implement this, but I wanted to make an automatic form AJAX-’ifier’ that could capture which submit button had caused the submit event to be fired too.

It’s implemented fairly simply:

$('form').ajaxify();

There’s a demo page or you can just download it and have a look.

Update: As pointed out by Andrea in the comments below, this would return the value of radio and checkboxes even if they weren’t selected. I have released 0.1a and updated the link above to fix this issue. Thanks Andrea!

Update 2: I have updated this plugin, view this post for more information.

I’ve been using the jQuery addCaptions plugin and have come across a couple of new features that I felt were required and have fixed a bug in the previous verison.

I have added an exclude option to the settings so you can prevent captions being added to elements not required (like a reCaptcha box…). It’s used like this:

$('div.demo').addCaptions({
  'exclude': {
    'alt': [
      /orange/
    ]
  }
});

This would exclude any images that have the word ‘orange’ in the the alt attribute.

I also fixed a minor bug in which the script would look for captions in elements in reverse order (whoops!).

The only other change is making the elements found within the container a selector instead of an element option and a class option.

There is an updated demo here, or you can just download the script here.

So I’ve updated the parallax script a little. It’s called in a more jQuery like manner now and has a couple of useful options for inverting the movement and changing the unit of measurement to any jQuery/CSS supported unit.

Example code:

$('div.parallax').parallax({
  'elements': [
    {
      'selector': 'body',
      'properties': {
        'x': {
          'background-position-x': {
            'initial': 0,
            'multiplier': 0.1,
            'invert': true
          }
        }
      }
    },
    {
      'selector': 'div.outer',
      'properties': {
        'x': {
          'background-position-x': {
            'initial': 50,
            'multiplier': 0.02,
            'unit': '%'
          }
        }
      }
    },
    {
      'selector': 'div.inner',
      'properties': {
        'x': {
          'background-position-x': {
            'initial': 0,
            'multiplier': 0.3
          }
        }
      }
    }
  ]
});

You can see a demo of the updated script, or just download the package (includes jQuery 1.3.2).

So I thought I’d update the JSS script I wrote previously with a few changes I’ve been thinking about for a while.

The primary reason for the update is to add a new ‘non-CSS’ property of ‘include’. This property allows you to include styles that have already been defined in the current class. read more…

Trackr is a very simple, lightweight (well, if you’re already using jQuery) user interaction tracker. It’s not particularly robust and is only in a fairly simple form right now.

The back end is written in PHP using MySQL for storage, but could easily be implemented in other languages.

To log data, you simply add a call to Trackr.init() to the page load event, passing the desired options as the only parameter to the function.

There are a variety of options that can be specified and for more information please see the test page.

You can get it here (includes jQuery 1.3.2).

I’ve seen some very cool parallax effect around lately, especially liking the Silverback site. But none of them are particularly interactive, so I thought I’d make a small implementation of the Parallax effect that interacts with the mouse.

Very early stages (and I haven’t tested it on IE yet… but you could just you conditional comments to exclude ‘those’ people anyway…) but it seems to be working ok. The options aren’t really simple, but they should be fairly self-explanatory…

Check out the demo (it is a very poor demo, please don’t look at the images, imagine it with a lovely hand drawn vector!) and get it here (minified).

Update: Created a quick demo of the silverback homepage with interactive parallax.

Update 2: Tested on IE8, seems to work fine!

Update 3: I have modified the script slightly, you can view the post here.

I’ve recently had to parse some pretty large XML documents, and needed a method to read one element at a time.

Here’s a fairly simple solution in PHP and Ruby form (hopefully a Python one coming soon…).

read more…