pipe.py: A simple functional list wrapper for python

main.py

from pipe import *

primes = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47]
mod_primes = ~(pipe(primes)
    | filter(lambda a: a > 20)
    | map(lambda a: a * a)
    | zip_index
)
summed_primes = ~(pipe(mod_primes) 
    | map(lambda a: a[1])
    | reduce(lambda a, b: a + b, 0)
)

print('primes: %s' % primes)
print('mutated primes: %s' % mod_primes)
print('sum: %s' % summed_primes)

pipe.py

class pipe(object):
    """pipe: a functional list wrapper"""
    def __init__(self, list):
        self.list = list

    def __or__(self, filterer):
        return pipe(filterer(self.list))

    def unwrap(self):
        return self.list

    def __invert__(self):
        return self.list

    def __repr__(self):
        return 'pipe('+ repr(self.list) +')'

def filter(func):
    def filterfn(list):
        return [x for x in list if func(x)]
    return filterfn

def map(func):
    def mapfn(list):
        return [func(x) for x in list]
    return mapfn

def reduce(func, initial=None):
    def reducefn(list, initial=initial):
        for item in list:
            initial = func(item, initial)
        return initial
    return reducefn

def zip(list):
    def zipfn(orig):
        return [(orig[i], list[i]) for i in xrange(min(len(list), len(orig)))]
    return zipfn

def flip(list):
    return [(j, i) for i, j in list]

def zip_index(list):
    # return [x for x in enumerate(list)]
    return ~(pipe(list) | zip(xrange(2**62)) | flip)

result.txt

primes: [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47]
mutated primes: [(0, 529), (1, 841), (2, 961), (3, 1369), (4, 1681), (5, 1849), (6, 2209)]
sum: 9439