+
+if ( ! function_exists( 'array_replace_recursive' ) ) :
+ /**
+ * PHP-agnostic version of {@link array_replace_recursive()}.
+ *
+ * The array_replace_recursive() function is a PHP 5.3 function. WordPress
+ * currently supports down to PHP 5.2, so this method is a workaround
+ * for PHP 5.2.
+ *
+ * Note: array_replace_recursive() supports infinite arguments, but for our use-
+ * case, we only need to support two arguments.
+ *
+ * Subject to removal once WordPress makes PHP 5.3.0 the minimum requirement.
+ *
+ * @since 4.5.3
+ *
+ * @see http://php.net/manual/en/function.array-replace-recursive.php#109390
+ *
+ * @param array $base Array with keys needing to be replaced.
+ * @param array $replacements Array with the replaced keys.
+ *
+ * @return array
+ */
+ function array_replace_recursive( $base = array(), $replacements = array() ) {
+ foreach ( array_slice( func_get_args(), 1 ) as $replacements ) {
+ $bref_stack = array( &$base );
+ $head_stack = array( $replacements );
+
+ do {
+ end( $bref_stack );
+
+ $bref = &$bref_stack[ key( $bref_stack ) ];
+ $head = array_pop( $head_stack );
+
+ unset( $bref_stack[ key( $bref_stack ) ] );
+
+ foreach ( array_keys( $head ) as $key ) {
+ if ( isset( $key, $bref ) &&
+ isset( $bref[ $key ] ) && is_array( $bref[ $key ] ) &&
+ isset( $head[ $key ] ) && is_array( $head[ $key ] )
+ ) {
+ $bref_stack[] = &$bref[ $key ];
+ $head_stack[] = $head[ $key ];
+ } else {
+ $bref[ $key ] = $head[ $key ];
+ }
+ }
+ } while ( count( $head_stack ) );
+ }
+
+ return $base;
+ }
+endif;
+
+// SPL can be disabled on PHP 5.2
+if ( ! function_exists( 'spl_autoload_register' ) ):
+ $_wp_spl_autoloaders = array();
+
+ /**
+ * Autoloader compatibility callback.
+ *
+ * @since 4.6.0
+ *
+ * @param string $classname Class to attempt autoloading.
+ */
+ function __autoload( $classname ) {
+ global $_wp_spl_autoloaders;
+ foreach ( $_wp_spl_autoloaders as $autoloader ) {
+ if ( ! is_callable( $autoloader ) ) {
+ // Avoid the extra warning if the autoloader isn't callable.
+ continue;
+ }
+
+ call_user_func( $autoloader, $classname );
+
+ // If it has been autoloaded, stop processing.
+ if ( class_exists( $classname, false ) ) {
+ return;
+ }
+ }
+ }
+
+ /**
+ * Registers a function to be autoloaded.
+ *
+ * @since 4.6.0
+ *
+ * @param callable $autoload_function The function to register.
+ * @param bool $throw Optional. Whether the function should throw an exception
+ * if the function isn't callable. Default true.
+ * @param bool $prepend Whether the function should be prepended to the stack.
+ * Default false.
+ */
+ function spl_autoload_register( $autoload_function, $throw = true, $prepend = false ) {
+ if ( $throw && ! is_callable( $autoload_function ) ) {
+ // String not translated to match PHP core.
+ throw new Exception( 'Function not callable' );
+ }
+
+ global $_wp_spl_autoloaders;
+
+ // Don't allow multiple registration.
+ if ( in_array( $autoload_function, $_wp_spl_autoloaders ) ) {
+ return;
+ }
+
+ if ( $prepend ) {
+ array_unshift( $_wp_spl_autoloaders, $autoload_function );
+ } else {
+ $_wp_spl_autoloaders[] = $autoload_function;
+ }
+ }
+
+ /**
+ * Unregisters an autoloader function.
+ *
+ * @since 4.6.0
+ *
+ * @param callable $function The function to unregister.
+ * @return bool True if the function was unregistered, false if it could not be.
+ */
+ function spl_autoload_unregister( $function ) {
+ global $_wp_spl_autoloaders;
+ foreach ( $_wp_spl_autoloaders as &$autoloader ) {
+ if ( $autoloader === $function ) {
+ unset( $autoloader );
+ return true;
+ }
+ }
+
+ return false;
+ }
+
+ /**
+ * Retrieves the registered autoloader functions.
+ *
+ * @since 4.6.0
+ *
+ * @return array List of autoloader functions.
+ */
+ function spl_autoload_functions() {
+ return $GLOBALS['_wp_spl_autoloaders'];
+ }
+endif;