gistfile1.aw

<?php
function named_args (array $args, array $settings = array())
{
    $native_types = array('boolean', 'integer', 'float', 'null', 'string', 'object', 'array', 'callable', 'resource');

    foreach ($settings AS $name => $arg)
    {
        $type     = NULL;
        $required = FALSE;
        
        if (is_int($name))
        {
            // It's an index of array
            $required = TRUE;
            $name     = $arg;
        }     

        if (strpos($name, ' ') !== FALSE)
        {
            // If there type definition
            $parts = explode(' ', $name);
            $type  = $parts[0];
            $name  = $parts[1];
        }

        /**
         * Defaults
         */

        if ( ! $required && ! array_key_exists($name, $args))
        {
            if ($required)
            {
                throw new Exception($name.' must be passed into function');
            }

            $args[$name] = $arg;
        }

        /**
         * Types
         */

        if ( ! empty($type))
        {
            if (array_key_exists($type, $native_types))
            {
                // Native type
                $function = ($type === 'boolean')
                    ? 'is_bool'
                    : 'is_'.$type;

                if ( ! $function($args[$name]))
                {
                    throw new Exception($name.' must be '.$type);
                }
            }
            elseif (is_object($args[$name]) && ! ($args[$name] instanceof $type))
            {
                // Class instance
                throw new Exception($name.' must be instance of '.$type);
            }
        }
    }

    return $args;
}