23 lines
539 B
Markdown
23 lines
539 B
Markdown
---
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title: none
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tags: list,function,intermediate
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---
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Returns `False` if the provided function returns `True` for at least one element in the list, `True` otherwise.
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Iterate over the elements of the list to test if every element in the list returns `False` based on `fn`.
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Omit the seconds argument, `fn`, to check if all elements are `False`.
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```py
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def none(lst, fn=lambda x: not not x):
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for el in lst:
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if fn(el):
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return False
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return True
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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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