pipe_in_python.py

pipe_in_python.py

from collections.abc import Callable, Iterable
from functools import partial

# See discussion in https://news.ycombinator.com/item?id=44942936
def pipe(orig, *transforms):
    result = orig

    for transform in transforms:
        if isinstance(transform, Callable):
            result = transform(result)
        else:
            assert isinstance(transform, Iterable)
            result = partial(*transform)(result)
    return result
    
# Example
times_two = lambda x: x * 2
plus_one = lambda x: x + 1
plus_c = lambda x, c: x + c

pipe(
    0,
    plus_one,
    times_two,
    
    # to supply positional args only, use a tuple
    (plus_c, 4),
    
    # to supply keyword args, use partial
    partial(plus_c, c=4)
)