23 lines
539 B
Markdown
23 lines
539 B
Markdown
---
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title: Test if every list element is falsy
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tags: list
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expertise: intermediate
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cover: blog_images/jars-on-shelf-2.jpg
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firstSeen: 2019-08-20T15:54:50+03:00
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lastUpdated: 2020-11-02T19:28:27+02:00
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---
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Checks if the provided function returns `True` for at least one element in the list.
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- Use `all()` and `fn` to check if `fn` returns `False` for all the elements in the list.
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```py
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def none(lst, fn = lambda x: x):
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return all(not fn(x) for x in lst)
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```
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```py
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none([0, 1, 2, 0], lambda x: x >= 2 ) # False
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none([0, 0, 0]) # True
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```
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