PhutilArrayWithDefaultValue.php
No OneTemporary
Actions

Subscribers

None

File Metadata

	<?php

	/**
	* Array-like object with a default value that is populated when nonexistent
	* keys are accessed. This is particularly useful to avoid constructs like this:
	*
	* $counts = array();
	* foreach ($fruit as $fruit) {
	* if (!isset($counts[$fruit])) {
	* $counts[$fruit] = 0;
	* }
	* $counts[$fruit] += 1;
	* }
	*
	* Instead, you can use PhutilArrayWithDefaultValue:
	*
	* $counts = new PhutilArrayWithDefaultValue();
	* foreach ($fruits as $fruit) {
	* $counts[$fruit] += 1;
	* }
	*
	* NOTE: You must use the `+= 1` operator, not `++`, because PHP is the crown
	* jewel of programming languages.
	*
	* Normally, the default value is `0` to allow the object to be used to count
	* things or build bitmasks. You can change the default with
	* @{method:setDefaultValue}.
	*
	* @group util
	*/
	final class PhutilArrayWithDefaultValue extends PhutilArray {

	private $defaultValue = 0;

	public function setDefaultValue($default_value) {
	$this->defaultValue = $default_value;
	return $this;
	}

	public function offsetExists($key) {
	return true;
	}

	public function offsetGet($key) {
	if (!parent::offsetExists($key)) {
	$this->offsetSet($key, $this->defaultValue);
	}
	return parent::offsetGet($key);
	}

	}