Returns the entity name of the current drawing's named object dictionary, which is the root of all nongraphical objects in the drawing
Prompts the user to select an object (entity) by specifying a point, and provides access to the definition data contained within a complex object
Provides similar functionality to that of the nentsel function without the need for user input
Begins a new dialog box and displays it, and can also specify a default action
Verifies that an item evaluates to nil
Returns the nth element of a list
Verifies that an item is bound to nil
Verifies that an item is a real number or an integer
