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pythonfunctional-programmingclojure

Clojure style function "threading" in Python

Clojure has a "->" macro which inserts each expression recursively as the first argument of the next expression.

This means that I could write:

(-> arg f1 f2 f3)

and it behaves like (shell piping):

f3(f2(f1(arg)))

I would like to do this in Python; however, searching seems to be a nightmare! I couldn't search for "->", and neither could I search for Python function threading!

Is there a way to overload, say, the | operator so that I could write this in Python?

arg | f1 | f2 | f3

Thanks!

Solution

  • You can easily implement something like this yourself.

    def compose(current_value, *args):
    for func in args:
        current_value = func(current_value)
    return current_value

def double(n):
    return 2*n

print compose(5, double, double) # prints 20