#summary Definition of thunks.
#labels Glossary

= Thunk =

A thunk is a [Arity nullary] (i.e. zero-argument) function that returns a constant that is bound to the lexical scope in which it is created. 

In Cat a thunk can be emulated using the [Quote quote instruction]:  

{{{
define thunk : ('a -> ( -> 'a))
{ quote }
}}}