Simple way of curryfying callables

[Gribouillis]

Currying is the process of transforming a function with signature e.g. (X, Y, Z) -> T into a function having signature X -> (Y -> (Z -> T)). For example the following spam() function

def spam(x, y, z):
    ...

is normally called with the syntax spam(7, 4, 3). A curried version would be called with the syntax spam(7)(4)(3).

The code below automates the process of currying the functions. It also provides a decorator to curryfy the functions as soon as they are defined.

__version__ = '2026.01.27'

class Curry:
    def __init__(self, arity, func, args: tuple=()):
        self.arity = arity
        self.func = func
        self.args = args

    def __repr__(self):
        return f'Curry({self.arity!r}, {self.func!r}, {self.args!r})'

    def __call__(self, arg):
        if self.arity == 1:
            return self.func(*self.args, arg)
        return Curry(self.arity - 1, self.func, self.args + (arg,))

curry = Curry(2, Curry)

@curry(3)
def spam(a, b, c):
    return ('result', a, b, c)

print(spam(7)(4)(3)) # prints ('result', 7, 4, 3)

Of course there are many modules devoted to this in the Cheese Shop.