Skip to main content

Python module for composing computations

Project description

FPy

version_badge

Functional Python

For better computation composing in Python

Goals

  • To bring the ability of composing computations in the functional way
  • Make my life easier

No Goals

  • Exact clone of Haskell
  • Blazing fast / super efficient

Python is Already Amazing, Why Bother?

  • Because I can
  • Python may be amazing in some field, but sucks from the functional perspective

Python Sucks, Why Bother?

  • Because I can
  • Python is still used in my work place

Install

With pip:

pip install fppy

Control:

Functor fpy.control.functor

Given Functors f, g:

  • __fmap__ :: f a -> (a -> b) -> f b
  • __ntrans__ :: f a -> (f a ~> g b) -> g b

Operators:

  • | = __fmap__
  • & = __ntrans__

Functions:

  • fmap = __fmap__

NTrans (Natrual Transform) fpy.control.natural_transform

Given Functors f, g:

  • __trans__ :: f a ~> g b

Applicative : Functor fpy.control.applicative

No new trait comparing to functor, liftA2 is defined using fmap

Monad : Applicative fpy.control.monad

Given Monad m:

  • __bind__ :: m a -> (a -> m b) -> m b

Operators:

  • >> = __bind__

Do Notation:

  • @do(Monad) enables do notation in the decorated function, where the explicit return statement will be treated as ret from the given Monad type, if no return statement is given, the last element on the stack will be returned.
  • name <- computation binds the computation to the following block, calling the __bind__ method of the monad object returned from computation with the name name.
  • (name1, name2, ..., namen) <- computation works in the similar way as the single name binding, this applys the binding function to the tuple contained within the monad object instead of calling the function directly.
  • name1, name2, ..., namen <- computation same as above

Data

Maybe : Monad fpy.data.maybe

Types:

  • Maybe[T]
  • Just[T] : Maybe[T]
  • Nothing[T] : Maybe[T]

Functions:

  • isJust :: Maybe[T] -> bool
  • isNothing :: Maybe[T] -> bool
  • fromJust :: Maybe[T] -> T
  • fromMaybe :: T -> Maybe[T] -> T
  • maybe :: S -> (T -> S) -> Maybe[T] -> S
  • mapMaybe :: (T -> Maybe[S]) -> List[T] -> List[S]

Either : Monad fpy.data.either

Types:

  • Either[T]
  • Left[T] : Either[T]
  • Right[T] : Either[T]

Forgetful : Monad (Forgetful Functor) fpy.data.forgetful

Types:

  • Under[T] Under similar to Haskell's Identity monad

Cont : Monad fpy.data.cont

Types:

  • Cont[T, R]

Functions:

  • cont :: (A -> B) -> Cont[A, B]
  • runCont :: Cout[B, C] -> C

Functions:

Given functor f: forget: NTrans[F, B, Under, T] :: f b ~> Under[T]

Utility Functions fpy.data.function

  • id_ :: T -> T
  • const :: T -> A -> T
  • flip :: (B -> A -> T) -> A -> B -> T
  • fix :: (A -> A) -> A
  • on :: (B -> B -> T) -> (A -> B) -> A -> A -> T

Slightly Dependent Utilities

-- not so well typed

NArg :: Nat -> Type
NArg (S Z) = A
NArg (S n) = A -> (NArg n)

NTpl :: (n:Nat) -> (NArg n) -> Type
NTpl (S Z) A =( A,)
NTpl (S n) (A -> NArg n) = cons A (NTpl n (NArg n))
  • constN :: (n:Nat) -> A -> (NArg n) -> A
  • uncurryN :: (n:Nat) -> args:(NArg n) -> A -> ((NTpl n args) -> A)

Composable

Composable fpy.composable.composable

  • __compose__

Operators:

  • ^ = __compose__

Transparent fpy.composable.transparent

  • __underlying__ Delegate an attribute access to an underlying object

Function fpy.composable.function

Types:

  • func : Composable
  • SignatureMismatchError
  • NotEnoughArgsError

Collections fpy.composable.collections

Types:

  • Seq : func
  • Map : func

Functions:

  • transN(n, f, it) := it[n] = f(it[n])
  • getN(n, it) := it[n]
  • setN(n, v, it) := it[n] = v
  • eqN(n, it, x) := it[n] == x
  • mapN(n, fn, lsts) := map(fn, zip(lst1, lst2 ... lstn))
  • of_(v1 ... vn) := _ in (v1 ... vn)
  • is_(t) := isinstance(_, t)
  • and_(a, b) := a(_) and b(_)
  • or_(a, b) := a(_) or b(_)
  • to(dst, src) := dst(src)
  • apply(fn) := fn(*a, **k)
  • fwd_ = Under.ret

Predefined Vars:

  • trans0
  • trans1
  • get0
  • get1
  • set0
  • set1
  • eq0
  • eq1
  • mp1
  • mp2

Parsec

Parsec fpy.parsec.parsec

Types:

  • parser[S, T] :: [S] -> Either [S] ([T] * [S])

Operators:

  • * = parser.timeN
  • + = parser.concat
  • | = parser.choice
  • >> = parser.parseR
  • << = parser.parseL

Functions:

  • one :: (S -> bool) -> parser[S, S]
  • neg :: (S -> bool) -> parser[S, S]
  • just_nothing :: parser[S, T]
  • pmaybe :: parser[S, T] -> parser[S, T]
  • many :: parser[S, T] -> parser[S, T]
  • many1 :: parser[S, T] -> parser[S, T]
  • ptrans :: parser[S, T] -> (T -> Y) -> parser[S, Y]
  • peek :: parser[S, T] -> parser[S, T]
  • skip :: parser[S, T] -> parser[S, T]
  • pseq :: [S] -> parser[S, T]
  • inv :: parser[S, T] -> parser[S, T]

Dependencies

License

GPL3+

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

fppy-0.0.18.post6.tar.gz (33.3 kB view details)

Uploaded Source

Built Distribution

fppy-0.0.18.post6-py3-none-any.whl (42.1 kB view details)

Uploaded Python 3

File details

Details for the file fppy-0.0.18.post6.tar.gz.

File metadata

  • Download URL: fppy-0.0.18.post6.tar.gz
  • Upload date:
  • Size: 33.3 kB
  • Tags: Source
  • Uploaded using Trusted Publishing? No
  • Uploaded via: twine/6.1.0 CPython/3.13.2

File hashes

Hashes for fppy-0.0.18.post6.tar.gz
Algorithm Hash digest
SHA256 480ad7a39a99ae2f3c90e24f259a4036ab544edd96a2be47efe8cc468fd67afe
MD5 c745b87f875e3efb75aaf83b243178d6
BLAKE2b-256 4dd20e47db3d7cdb8defb45df2ba592d8fbd68e602205f593cc2f94e895f813d

See more details on using hashes here.

File details

Details for the file fppy-0.0.18.post6-py3-none-any.whl.

File metadata

  • Download URL: fppy-0.0.18.post6-py3-none-any.whl
  • Upload date:
  • Size: 42.1 kB
  • Tags: Python 3
  • Uploaded using Trusted Publishing? No
  • Uploaded via: twine/6.1.0 CPython/3.13.2

File hashes

Hashes for fppy-0.0.18.post6-py3-none-any.whl
Algorithm Hash digest
SHA256 dd2a3791db57dabf54ca3ed9af02c8c1e62a4d8e39a16f9521b0b89c1a3c8cf3
MD5 3ae7591103eafb618f609387aa950c21
BLAKE2b-256 6bbf763d7265c9368f912eed6e5d3403261e95d882934b02b16826996b6bf392

See more details on using hashes here.

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page