# `None` means `lambda x: x` here I find it more helpful to think of it as meani... | Hacker News

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		euccastro on Dec 24, 2008 \| parent \| context \| favorite \| on: Why Learning Haskell/Python Makes You a Worse Prog... # `None` means `lambda x: x` here I find it more helpful to think of it as meaning `bool` in that context. I think the None special case is only there because filter() predates bool() in Python.

d0mine on Dec 24, 2008 [–]

Thanks. `bool` is more readable.

  "\n".join(filter(bool, descriptions))

Or `len`

  "\n".join(filter(len, descriptions))

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