(PHP 5, PHP 7) Gets extension info public ReflectionExtension

(PHP 4, PHP 5, PHP 7) Return an array with elements in reverse order

(PHP 4, PHP 5, PHP 7) Gets the class methods' names

(PHP 4, PHP 5, PHP 7) Get the default properties of the class

(PHP 5, PHP 7) Checks if class is defined internally by an extension, or the core

(PHP 4, PHP 5, PHP 7) Fetch a key from an array

(PHP 5 >= 5.4.0, PHP 7) Checks if the trait exists

(PHP 4 >= 4.0.4, PHP 5, PHP 7) Check for any printable character(s) except space

(PHP 5, PHP 7) Checks if method is abstract public

(PHP 4 >= 4.0.5, PHP 5, PHP 7) Finds whether a variable is a scalar