freer-indexed: Freer indexed monad for type-level resource-aware effectual operations.

[ bsd3, effects, library ] [ Propose Tags ]

This package defines "freer indexed monad". It combines the ideas of freer monad and indexed (aka parameterized) monad:

It allows defining indexed monadic computations as GADTs without making them into ad-hoc indexed monads, and instead use this data type to convert them into Functor, XApplicative and XMonad instances - see Control.XApplicative and Control.XMonad in this package.

This package does not (yet) allow composing these computations.

Semantically, these computations could represent type-level state changes of some associated resources, with the first index parameter meaning initial resource state prior to the computation, and the second index - the final resource state, making each computation an edge in the graph of resource state transitions.

For XApplicative/XMonad classes all class and additional functions have similar names to standard Applicative/Monad functions, following two naming conventions:

  • function names are prefixed with "x" (for "indeXed") - e.g. xpure, xreturn, xliftM2 etc.

  • operators are postfixed with ":" - e.g. <*>:, >>=:, >=>: etc.

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Dependencies base (>=4.7 && <5) [details]
License BSD-3-Clause
Copyright 2020 Evgeny Poberezkin
Author Evgeny Poberezkin
Category Effects
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Source repo head: git clone
Uploaded by epoberezkin at 2020-07-07T13:07:24Z
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Reverse Dependencies 1 direct, 0 indirect [details]
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Status Docs available [build log]
Last success reported on 2020-07-07 [all 1 reports]

Readme for freer-indexed-

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Freer indexed (parameterized) monad for type-level resource-aware effectual operations.

See Parameterized Extensible Effects and Session Types.

See docs on hackage.