128 lines
4.6 KiB
Text
128 lines
4.6 KiB
Text
Metadata-Version: 2.1
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Name: OSlash
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Version: 0.6.3
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Summary: OSlash (Ø) for Python 3.8+
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Home-page: https://github.com/dbrattli/oslash
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Author: Dag Brattli
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Author-email: dag@brattli.net
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License: MIT License
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Download-URL: https://github.com/dbrattli/oslash
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Platform: UNKNOWN
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Classifier: Development Status :: 4 - Beta
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Classifier: Environment :: Other Environment
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Classifier: Intended Audience :: Developers
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Classifier: License :: OSI Approved :: MIT License
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Classifier: Operating System :: OS Independent
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Classifier: Programming Language :: Python :: 3.8
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Classifier: Programming Language :: Python :: 3.9
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Classifier: Topic :: Software Development :: Libraries :: Python Modules
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Description-Content-Type: text/markdown
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Requires-Dist: typing-extensions
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# Functors, Applicatives, And Monads in Python
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OSlash (Ø) is a library for playing with functional programming in Python 3.8+. It's an attempt to re-implement some of
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the code from [Learn You a Haskell for Great Good!](http://learnyouahaskell.com/) in Python 3.8. OSlash unifies
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functional and object oriented paradigms by grouping related functions within classes. Objects are however never used
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for storing values or mutable data, and data only lives within function closures.
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OSlash is intended to be a tutorial. For practical functional programming in Python in production environments you
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should use [FSlash](https://github.com/dbrattli/fslash) instead.
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## Install
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```bash
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> pip3 install oslash
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```
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The project currently contains implementations for:
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## Abstract Base Classes
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- **[Functor](https://github.com/dbrattli/OSlash/wiki/Functors,-Applicatives,-And-Monads-In-Pictures#functors)**, for stuff that can be mapped
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- **[Applicative](https://github.com/dbrattli/OSlash/wiki/Functors,-Applicatives,-And-Monads-In-Pictures#applicatives)**, for callable stuff
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- **Monoid**, for associative stuff
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- **[Monad](https://github.com/dbrattli/OSlash/wiki/Functors,-Applicatives,-And-Monads-In-Pictures#monads)**, for monadic stuff
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## And Some Monads
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- **Identity**, boxed stuff in its simplest form
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- **[Maybe (Just | Nothing)](https://github.com/dbrattli/oslash/wiki/Functors,-Applicatives,-And-Monads-In-Pictures)**, for optional stuff
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- **Either (Right | Left)**, for possible failures
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- **List**, purely functional list of stuff
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- **[IO Action](https://github.com/dbrattli/OSlash/wiki/Functors,-Applicatives,-And-Monads-In-Pictures#io-monad)**, for impure stuff
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- **[Writer](https://github.com/dbrattli/OSlash/wiki/Three-Useful-Monads#the-writer-monad)**, for logging stuff
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- **[Reader](https://github.com/dbrattli/OSlash/wiki/Three-Useful-Monads#the-reader-monad)**, for callable stuff
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- **State**, for stateful computations of stuff
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- **Cont**, for continuation of stuff
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## Monadic functions
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- **>>**, for sequencing monadic actions
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- **lift**, for mapping a function over monadic values
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- **join**, for removing one level of monadic structure
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- **compose**, for composing monadic functions
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## Utility functions
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- **compose**, for composing 0 to n functions
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## But why?
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Yes, I know there are other projects out there like [PyMonad](https://bitbucket.org/jason_delaat/pymonad/),
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[fn.py](https://github.com/kachayev/fn.py). I'm simply doing this in order to better understand the
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[book](http://learnyouahaskell.com/). It's so much easier to learn when you implement things yourself. The code may be
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similar to PyMonad in structure, but is quite different in implementation.
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Why is the project called OSlash? OSlash is the Norwegian character called [Oslash](http://en.wikipedia.org/wiki/Ø).
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Initially I wanted to create a project that used Ø and ø (unicode) for the project name and modules. It didn't work out
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well, so I renamed it to OSlash.
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## Examples
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Haskell:
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```haskell
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> fmap (+3) (Just 2)
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Just 5
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> (+3) <$> (Just 2)
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Just 5
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```
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Python:
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```python
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>>> Just(2).map(lambda x: x+3)
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Just 5
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>>> (lambda x: x+3) % Just(2)
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Just 5
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```
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IO Actions:
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```python
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from oslash import put_line, get_line
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main = put_line("What is your name?") | (lambda _:
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get_line() | (lambda name:
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put_line("What is your age?") | (lambda _:
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get_line() | (lambda age:
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put_line("Hello " + name + "!") | (lambda _:
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put_line("You are " + age + " years old"))))))
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if __name__ == "__main__":
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main()
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```
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## Tutorials
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- [Functors, Applicatives, And Monads In Pictures](https://github.com/dbrattli/oslash/wiki/Functors,-Applicatives,-And-Monads-In-Pictures) in Python.
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- [Three Useful Monads](https://github.com/dbrattli/OSlash/wiki/Three-Useful-Monads) _(in progress)_
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- [Using Either monad in Python](https://medium.com/@rnesytov/using-either-monad-in-python-b6eac698dff5)
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