churry

Warning

This library does not comply with the Python philosophy TIOOTDI. Leave before you faint.

Introduction

The word churry is the combination of chain and curry, which implies that the library named as such does the same.

Affirmative to that. This library enables you to make a function chainable and curriable.

chainability

Suppose we have a function:

def move(ball, from_=0, to=10):
    pass

Normally, we would

move(spam, 1, 5)
# or
move(spam, from_=1, to=5)

Now, with the churry decorator

from churry import churried

@churried()
def move(ball, from_=0, to=10):
    pass

we can

move.from_(1).to(5)(spam)

Note that for functions with variable arguments (both positional or keyword), churry wouldn't know when to stop receiving arguments. So you have to call the churried function with empty argument to inform churry that it's time to evaluate. For example,

@churried()
def move_simultaneously(*balls, from_=0, to=10)
    pass

move_simultaneously(foo, bar).from_(1).to(5)()
# or
move_simultaneously.from_(1).to(5)(foo, bar)()

curriability

With immutable churry, you can

move_to_1_5 = move_simultaneously.from_(1).to(5)

move_to_1_5(foo, bar)()
move_to_1_5(bar, foo)()
move_to_1_5(spam, ham)()

I may have wrongly used the terms chain and curry, but that's not important (at least to me). What's important now is that you can churry a function.

Gotchas

If the function you want to decorate does not have variable positional or variable keyword argument, you must supply the keyword arguments before the positional arguments are supplied. Because when positional arguments are fully supplied, churry evaluates the function with the default argument values.

In short, do

move.from_(1).to(5)(spam)
# or
move.to(5).from_(1)(spam)

Do not

move(spam).from_(1).to(5)
# this raises AttributeError because NoneType (return value of move(spam))
# does not have attribute 'from_'

If you do not want this feature (or whatever it is), use the explicit switch so that churry only does evaluation after you call it with empty argument.

Examples

See tests.py.

See also

Please check out the other branch of this project mutable-churry, pay attention to section curriability.

License

This library is licensed under GPLv3.