# Reverse compose functions

Python, Function · Nov 2, 2020

Performs left-to-right function composition.

- Use
`functools.reduce()`

to perform left-to-right function composition. - The first (leftmost) function can accept one or more arguments; the remaining functions must be unary.

```
from functools import reduce
def compose_right(*fns):
return reduce(lambda f, g: lambda *args: g(f(*args)), fns)
```

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