Monads for behaviour
<p>The monads used to model effectful computations traditionally concentrate on the &apos;destination&apos;—the final results of the program. However, sometimes we are also interested in the &apos;journey&apos;—the intermediate course of a computation—especially...
| Main Authors: | , |
|---|---|
| Format: | Journal article |
| Language: | English |
| Published: |
2013
|
| Subjects: |
| Summary: | <p>The monads used to model effectful computations traditionally concentrate on the &apos;destination&apos;—the final results of the program. However, sometimes we are also interested in the &apos;journey&apos;—the intermediate course of a computation—especially when reasoning about non-terminating interactive systems. In this article we claim that a necessary property of a monad for it to be able to describe the behaviour of a program is complete iterativity. We show how an ordinary monad can be modified to disclose more about its internal computational behaviour, by applying an associated transformer to a completely iterative monad. To illustrate this, we introduce two new constructions: a coinductive cousin of Cenciarelli and Moggi&apos;s generalised resumption transformer, and States—a State-like monad that accumulates the intermediate states.</p> |
|---|