Objects are general-purpose values. There are two objects in the core language: the file object, and the general-purpose object. Objects may also be used when the language is used to extend another program to represent concepts from that program. In this case, the program may define the object's behaviour. Generally, an object exhibits the basic behaviour of both a list and a function.

A value of the object type is a reference to an underlying object, and when it is copied the result points to the same object.

Yewslip> a = lib.object(`x = 1)

Yewslip> b = a

Yewslip> a.x = 2

Yewslip> print b.x
2