DZone Snippets: php code

Flattening an array of arrays in PHP

keith (Keith Gaughan) — Tue, 16 Oct 2007 08:30:23 GMT

It does just what it says on the tin:



/** Denests the nested arrays within the given array. */

function flatten_array(array $a) {

    $i = 0;

    while ($i < count($a)) {

        if (is_array($a[$i])) {

            array_splice($a, $i, 1, $a[$i]);

        } else {

            $i++;

        }

    }

    return $a;

}

With added unit-testy goodness:



class FlattenTest extends PHPUnit_Framework_TestCase {



    public function test_flatten() {

        $this->assertEquals(array(), flatten_array(array()));

        $this->assertEquals(array(1), flatten_array(array(1)));

        $this->assertEquals(array(1), flatten_array(array(array(1))));

        $this->assertEquals(array(1, 2), flatten_array(array(array(1, 2))));

        $this->assertEquals(array(1, 2), flatten_array(array(array(1), 2)));

        $this->assertEquals(array(1, 2), flatten_array(array(1, array(2))));

        $this->assertEquals(array(1, 2, 3), flatten_array(array(1, array(2), 3)));

        $this->assertEquals(array(1, 2, 3, 4), flatten_array(array(1, array(2, 3), 4)));

    }

}

Value coalescence in PHP

keith (Keith Gaughan) — Tue, 13 Mar 2007 11:00:32 GMT

Here's something I keep on having to do in PHP and other languages. Often I need to find the first non-empty value from a set of arguments. Here's how I do it.



function coalesce() {

    $args = func_get_args();

    foreach ($args as $arg) {

        if (!empty($arg)) {

            return $arg;

        }

    }

    return $args[0];

}

The function assumes that it will be called with at least one value. It can be trivially altered to use is_null() instead if that suits.

An analogue of ColdFusion's CFPARAM tag in PHP.

keith (Keith Gaughan) — Sat, 23 Jul 2005 03:14:00 GMT



/**

 * Checks if $var is already defined and if not, sets it to

 * $default.

 *

 * @param  $var         Variable to check.

 * @param  $default     Value to give the checked variable if

 *                      found to be null; "" by default.

 * @param  $catchNulls  TRUE: treat empty strings as null; FALSE

 *                      by default.

 *

 * @note   It's a lot like ColdFusion's  tag.

 */

function set_default(&$var, $default="", $catchNulls=FALSE) {

    if (!isset($var) || ($catchNulls && $var == "")) {

        $var = $default;

    }

}

This appears to have stopped working as of PHP 5.

The world's simplest (decent) PHP templating engine...

keith (Keith Gaughan) — Fri, 22 Jul 2005 07:02:14 GMT

...is PHP, so why not use it?



function include_view($__view, $vars=NULL) {

    # Start buffering the generated text.

    ob_start();



    # Process the view.

    if (!is_null($vars)) {

        extract($vars, EXTR_OVERWRITE | EXTR_REFS);

    }

    include("views/$__view.php");



    # Grab the generated content and clean up.

    $content = ob_get_contents();

    ob_end_clean();



    return $content;

}