Reverse Compose Functions: A Functional Programming Challenge

Introduction

Function composition is a technique used in functional programming to combine two or more functions to create a new function. In Python, we can use the compose function from the functools module to perform function composition. However, the compose function performs right-to-left function composition, which may not be suitable for all use cases. In this challenge, you will implement a function that performs left-to-right function composition.

Skills Graph

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Reverse Compose Functions

Problem

Write a function compose_right that takes one or more functions as arguments and returns a new function that performs left-to-right function composition. The first (leftmost) function can accept one or more arguments; the remaining functions must be unary.

Your implementation should use the reduce function from the functools module to perform left-to-right function composition.

from functools import reduce def compose_right(*fns): ## your code here

Example

add = lambda x, y: x + y square = lambda x: x * x add_and_square = compose_right(add, square) assert add_and_square(1, 2) == 9

In the example above, we define two functions add and square. We then use the compose_right function to create a new function add_and_square that first adds two numbers and then squares the result. We then call the add_and_square function with the arguments 1 and 2, which returns 9.

Reverse Compose Functions | Challenge

Introduction

Skills Graph