Fix a few typos and add a backport (compat) for hex2bin()
diff --git a/system/core/compat/standard.php b/system/core/compat/standard.php
new file mode 100644
index 0000000..6380fa1
--- /dev/null
+++ b/system/core/compat/standard.php
@@ -0,0 +1,293 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP 5.2.4 or newer
+ *
+ * NOTICE OF LICENSE
+ *
+ * Licensed under the Open Software License version 3.0
+ *
+ * This source file is subject to the Open Software License (OSL 3.0) that is
+ * bundled with this package in the files license.txt / license.rst. It is
+ * also available through the world wide web at this URL:
+ * http://opensource.org/licenses/OSL-3.0
+ * If you did not receive a copy of the license and are unable to obtain it
+ * through the world wide web, please send an email to
+ * licensing@ellislab.com so we can send you a copy immediately.
+ *
+ * @package CodeIgniter
+ * @author EllisLab Dev Team
+ * @copyright Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/)
+ * @license http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
+ * @link http://codeigniter.com
+ * @since Version 3.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * PHP ext/standard compatibility package
+ *
+ * @package CodeIgniter
+ * @subpackage CodeIgniter
+ * @category Compatibility
+ * @author Andrey Andreev
+ * @link http://codeigniter.com/user_guide/
+ */
+
+// ------------------------------------------------------------------------
+
+if (is_php('5.5'))
+{
+ return;
+}
+
+// ------------------------------------------------------------------------
+
+if ( ! function_exists('array_column'))
+{
+ /**
+ * array_column()
+ *
+ * @link http://php.net/array_column
+ * @param string $array
+ * @param mixed $column_key
+ * @param mixed $index_key
+ * @return array
+ */
+ function array_column(array $array, $column_key, $index_key = NULL)
+ {
+ if ( ! in_array($type = gettype($column_key), array('integer', 'string', 'NULL'), TRUE))
+ {
+ if ($type === 'double')
+ {
+ $column_key = (int) $column_key;
+ }
+ elseif ($type === 'object' && method_exists($column_key, '__toString'))
+ {
+ $column_key = (string) $column_key;
+ }
+ else
+ {
+ trigger_error('array_column(): The column key should be either a string or an integer', E_USER_WARNING);
+ return FALSE;
+ }
+ }
+
+ if ( ! in_array($type = gettype($index_key), array('integer', 'string', 'NULL'), TRUE))
+ {
+ if ($type === 'double')
+ {
+ $index_key = (int) $index_key;
+ }
+ elseif ($type === 'object' && method_exists($index_key, '__toString'))
+ {
+ $index_key = (string) $index_key;
+ }
+ else
+ {
+ trigger_error('array_column(): The index key should be either a string or an integer', E_USER_WARNING);
+ return FALSE;
+ }
+ }
+
+ $result = array();
+ foreach ($array as &$a)
+ {
+ if ($column_key === NULL)
+ {
+ $value = $a;
+ }
+ elseif (is_array($a) && array_key_exists($column_key, $a))
+ {
+ $value = $a[$column_key];
+ }
+ else
+ {
+ continue;
+ }
+
+ if ($index_key === NULL OR ! array_key_exists($index_key, $a))
+ {
+ $result[] = $value;
+ }
+ else
+ {
+ $result[$a[$index_key]] = $value;
+ }
+ }
+
+ return $result;
+ }
+}
+
+// ------------------------------------------------------------------------
+
+if (is_php('5.4'))
+{
+ return;
+}
+
+// ------------------------------------------------------------------------
+
+if ( ! function_exists('hex2bin'))
+{
+ /**
+ * hex2bin()
+ *
+ * @link http://php.net/hex2bin
+ * @param string $data
+ * @return string
+ */
+ function hex2bin($data)
+ {
+ if (in_array($type = gettype($data), array('array', 'double', 'object'), TRUE))
+ {
+ if ($type === 'object' && method_exists($data, '__toString'))
+ {
+ $data = (string) $data;
+ }
+ else
+ {
+ trigger_error('hex2bin() expects parameter 1 to be string, '.$type.' given', E_USER_WARNING);
+ return NULL;
+ }
+ }
+
+ if (strlen($data) % 2 !== 0)
+ {
+ trigger_error('Hexadecimal input string must have an even length', E_USER_WARNING);
+ return FALSE;
+ }
+ elseif ( ! preg_match('/^[0-9a-f]*$/i', $data))
+ {
+ trigger_error('Input string must be hexadecimal string', E_USER_WARNING);
+ return FALSE;
+ }
+
+ return pack('H*', $data);
+ }
+}
+
+// ------------------------------------------------------------------------
+
+if (is_php('5.3'))
+{
+ return;
+}
+
+// ------------------------------------------------------------------------
+
+if ( ! function_exists('array_replace'))
+{
+ /**
+ * array_replace()
+ *
+ * @link http://php.net/array_replace
+ * @return array
+ */
+ function array_replace()
+ {
+ $arrays = func_get_args();
+
+ if (($c = count($arrays)) === 0)
+ {
+ trigger_error('array_replace() expects at least 1 parameter, 0 given', E_USER_WARNING);
+ return NULL;
+ }
+ elseif ($c === 1)
+ {
+ if ( ! is_array($arrays[0]))
+ {
+ trigger_error('array_replace(): Argument #1 is not an array', E_USER_WARNING);
+ return NULL;
+ }
+
+ return $arrays[0];
+ }
+
+ $array = array_shift($arrays);
+ $c--;
+
+ for ($i = 0; $i < $c; $i++)
+ {
+ if ( ! is_array($arrays[$i]))
+ {
+ trigger_error('array_replace(): Argument #'.($i + 2).' is not an array', E_USER_WARNING);
+ return NULL;
+ }
+ elseif (empty($arrays[$i]))
+ {
+ continue;
+ }
+
+ foreach (array_keys($arrays[$i]) as $key)
+ {
+ $array[$key] = $arrays[$i][$key];
+ }
+ }
+
+ return $array;
+ }
+}
+
+// ------------------------------------------------------------------------
+
+if ( ! function_exists('array_replace_recursive'))
+{
+ /**
+ * array_replace_recursive()
+ *
+ * @link http://php.net/array_replace_recursive
+ * @return array
+ */
+ function array_replace_recursive()
+ {
+ $arrays = func_get_args();
+
+ if (($c = count($arrays)) === 0)
+ {
+ trigger_error('array_replace_recursive() expects at least 1 parameter, 0 given', E_USER_WARNING);
+ return NULL;
+ }
+ elseif ($c === 1)
+ {
+ if ( ! is_array($arrays[0]))
+ {
+ trigger_error('array_replace_recursive(): Argument #1 is not an array', E_USER_WARNING);
+ return NULL;
+ }
+
+ return $arrays[0];
+ }
+
+ $array = array_shift($arrays);
+ $c--;
+
+ for ($i = 0; $i < $c; $i++)
+ {
+ if ( ! is_array($arrays[$i]))
+ {
+ trigger_error('array_replace_recursive(): Argument #'.($i + 2).' is not an array', E_USER_WARNING);
+ return NULL;
+ }
+ elseif (empty($arrays[$i]))
+ {
+ continue;
+ }
+
+ foreach (array_keys($arrays[$i]) as $key)
+ {
+ $array[$key] = (is_array($arrays[$i][$key]) && isset($array[$key]) && is_array($array[$key]))
+ ? array_replace_recursive($array[$key], $arrays[$i][$key])
+ : $arrays[$i][$key];
+ }
+ }
+
+ return $array;
+ }
+}
+
+/* End of file array.php */
+/* Location: ./system/core/compat/array.php */
\ No newline at end of file