Lightweight array dot notation

by adael
I've made some functions to speedup the work with arrays in dotted notation.

First of all: i'm spanish, so excuse syntax/errors (thanks you).

I think the Cakephp Set class does a great job, but it's slow if you need to use it into many iterations.

For simple dotted access to arrays here you have a set of functions that works and do it fast (more than 10x faster than Cakephp according to my tests).

The functions are so simple, only works with simple dotted notation, for example '', or 'My.verylong.path.variable', but not with 'Customers.{n}.name', or xpath, the huge amount of functionality that Set class have may stay in Set class. My functions are for some concrete situations.

I hope the code helps the cakephp comunity.

Functions and usage:

// Note that the array is passed by reference.
dget(&$arr, $path); // returns the value or null if not exists
// Example:
$a = array('Customers' => array(1 => array('name' => 'john')));
echo dget($a, ''); // prints 'john'

dset(&$arr, $path, $val); // set the value into the path
// Example:
$a = array();
dset($a, '', 'john');
print_r($a); // give array('Customers' => array(1 => array('name' => 'john')));    

dcount(&$arr, $path); // returns the number of items (if any) null otherwise    
// Example:
$a = array('Fruits' => array('pear', 'orange', 'lemon', 'watermelon'));
echo dcount($a, 'Fruits'); // return 4

ddel(&$arr, $path); // removes the item in the path if exists
// Example:
$a = array('Customers' => array(1 => array('name' => 'john', 'email' => '')));
ddel($a, ''); // now the email key is deleted.

I preferred to use functions instead of a static class for speed, but you can easily to put the functions into a class and turn them static (and rename them to get, set, count and del).

With the pattern of these functions, some more can (and should) be created.

How fast are the functions

// with: 
$array = array('key1' => array('key2' => array('key3' => 8)));
// The native way: 
echo $array['key1']['key2']['key3']; 
// => 1x
// With dget(): 
echo dget($array, 'key1.key2.key3'); 
// => 12x times slower
// With cakephp set::classicExtract
$array = Set::classicExtract($array, 'key1.key2.key3'); 
// => more than 100x times slower

The code

Please, comment for (more than possible) bugs, or improvements. I hope this code helps cakephp comunity. Greetings.


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