Inheritance

From Impure Wiki

In impure, like in many object-oriented programming languages, there is inheritance. What's the meaning of that? Well, in the same way that cats are felines, a NumberList data structure is also a List. Another way of saying it is that NumberList inherits from List - is a case or type of List.

One important consequence of this fact is that any inlet that takes a List will also accept a NumberList (and StringList, DateList, Table... In Impure, even a Polygon is a List (of Points))

The example on the image shows how a NumberList is reversed. The operator reverseList takes a List as input. It can reverse any kind of List.

Inheritance explains why in some cases the icons of an outlet and an inlet linked by a connection don't match.