Coconut

Coconut is a simple, elegant, Pythonic functional programming language that compiles to Python. Since all valid Python is valid Coconut, joining the over 30,000 people already using Coconut will only extend and enhance what you're already capable of in Python.

Why use Coconut? Coconut is built to be fundamentally useful. Coconut enhances the repertoire of Python programmers to include the tools of modern functional programming, in such a way that those tools are easy to use and immensely powerful; that is, Coconut does to functional programming what Python did to imperative programming. And Coconut code runs the same on any Python version, making the Python 2/3 split a thing of the past.

Installing Coconut is as easy as

installing Python,
opening a command-line prompt,
and entering:

python -m pip install coconut

which will give you access to all the features of Coconut, which adds to Python built-in, syntactical support for:

pipeline-style programming

"hello, world!" |> print

prettier lambdas

(x) -> x ** 2

partial application

range(10) |> map$((x) -> x ** 2) |> list

pattern-matching

match [head] + tail in [0, 1, 2, 3]:
    print(head, tail)

destructuring assignment

{"list": [0] + rest} = {"list": [0, 1, 2, 3]}

infix notation

5 `mod` 3 == 2

algebraic data types

data vec2(x, y):
    def __eq__(self, other):
        match vec2(=self.x, =self.y) in other:
            return True
        else:
            return False

operator functions

range(15) |> map$((*)$(2)) |> list

function composition

f .. g .. h (x, y, z)

lazy lists

(| first_elem() |) :: rest_elems()

parallel programming

range(100) |> parallel_map$((**)$(2)) |> list

tail recursion optimization

@recursive
def factorial(n):
    case n:
        match 0:
            return 1
        match _ is int if n > 0:
            return n * factorial(n - 1)

and much more!

Ready to get started? Here are some links to help you out:

Coconut's tutorial will guide you through the process of starting to enhance your Python with Coconut in a straightforward, easy-to-follow way.
Coconut's documentation is an extensive catalog of information on all of Coconut's features for whenever you see something that you want more information about.
The Coconut FAQ should hopefully answer any questions you might have about who Coconut is built for and whether or not you should use it.
Creating a new issue is the best way for you to get help if you're having a problem with Coconut—just detail the problem in the issue and it will be addressed as soon as possible.
Coconut's chat room is a great place if you want to pose any general questions, concerns, or comments you have about Coconut to other Coconut developers.

Coconut

Simple, elegant, Pythonic functional programming.

Coconut