28 lines
625 B
Markdown
28 lines
625 B
Markdown
---
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title: Compose functions
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type: snippet
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language: python
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tags: [function]
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cover: tram-car-2
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dateModified: 2020-11-02T19:27:07+02:00
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---
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Performs right-to-left function composition.
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- Use `functools.reduce()` to perform right-to-left function composition.
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- The last (rightmost) function can accept one or more arguments; the remaining functions must be unary.
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```py
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from functools import reduce
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def compose(*fns):
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return reduce(lambda f, g: lambda *args: f(g(*args)), fns)
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```
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```py
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add5 = lambda x: x + 5
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multiply = lambda x, y: x * y
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multiply_and_add_5 = compose(add5, multiply)
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multiply_and_add_5(5, 2) # 15
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```
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