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The latest and greatest version of jQuery, version 1.4, was released on January 14, the birthday of jQuery’s original launch. Bugfixes and improvements abound!

The jQuery team has put together a site devoted to the new version, called the 14 days of jQuery, covering the major version changes as well as infrastructure updates coinciding with the new release. For example, the documentation site has been completely redesigned, and been moved to it’s own subdomain home, api.jquery.com. Links from the primary jquery.com site should be updated within the next week. With video demos of new features, Q&A’s with the core team (including founder John Resig), it’s well-worth checking out for every jQuery developer.

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If you need to change the timezone of a Debian system, your searches will probably tell you to use the tzselect utility. That will only change the timezone for the server temporarily. Use that command and then run this:

cat /etc/timezone

See how the timezone didn’t change? Left alone, the system will revert to the timezone stored in /etc/timezone at next reboot.

Plus, tzselect does not offer the full compliment of possible timezones. I recently needed to change my server to GMT, for example, and tzselect does not include an option for it.

Instead, Debian has a less-publicized tool that will solve both problems…

dpkg-reconfigure tzdata

Run that command and it will permanently change the timezone for the system, and includes options for all sort of obscure timezones. I wouldn’t consider GMT to be obscure, but maybe that’s just me.

Took me forever to find this searching earlier today. I don’t know why this isn’t more widely noted, but there you go.

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Core PHP does not include a define_once() function to complement functions like require_once() and include_once(), which is pretty silly in my opinion. While I am generally not a fan of using *_once statements due to the performance penalty (and incurred laziness), define_once is the exception. There are ways to look for a loaded/missing file, but a define is not a define until you define it, so you really have no choice.

So in situations where you have to blindly load defines — I do it to build language defines in a cascading templating system — use this function to achieve the proper results:

function define_once($define, $value) {
  if (!defined((string)$define)) {
    define($define, $value);
    return true;
  }
  return false;
}

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PHP includes some handy functions to find the first or last occurrence of a given string token in a string: strpos and strrpos. However these functions are limited to just the first occurrence; what if I want to know the location of the second token’s position, or the third? These problems usually result in some serious coding acrobatics.

Well no need for code-jitsu anymore. Based almost completely on a post I found at another blog — which is now down, how’s that for timing? — here are two functions which allow you to search for any occurrence of a specific token in a string…

/**
 * Find position of Nth $occurrence of $needle in $haystack
 * Starts from the beginning of the string
**/
function strpos_offset($needle, $haystack, $occurrence) {
  // explode the haystack
  $arr = explode($needle, $haystack);
  // check the needle is not out of bounds
  switch( $occurrence ) {
    case $occurrence == 0:
      return false;
    case $occurrence > max(array_keys($arr)):
      return false;
    default:
      return strlen(implode($needle, array_slice($arr, 0, $occurrence)));
  }
}
 
/**
 * Find position of Nth $occurrence of $needle in $haystack
 * Starts from the end of the string
**/
function strrpos_offset($needle, $haystack, $occurrence) {
  // explode the haystack
  $arr = array_reverse(explode($needle, $haystack));
  // check the needle is not out of bounds
  switch( $occurrence ) {
    case $occurrence == 0:
      return false;
    case $occurrence > max(array_keys($arr)):
      return false;
    default:
      $inverted = strlen(implode($needle, array_slice($arr, 0, $occurrence)));
      $actual = (strlen($haystack) - 1) - $inverted;
      return $actual;
  }
}
 
// look for second occurrence of letter 'a' from the start of string
echo strpos_offset('a', 'abracadabra', 2);
// returns 3
 
// look for second occurrence of letter 'a' from the end of string
echo strrpos_offset('a', 'abracadabra', 2);
// returns 7

In terms of use, we’ve essentially added an extra argument to strpos and strrpos that specifies which occurrence you’re looking for. In other words, you can make both of these functions work like the PHP standards by setting the third $occurrence variable to 1.

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