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#6 is really confusing. Whenever I encounter something like this my first reaction is that whenever possible such obscure components of a language should be avoided and more verbose/clear code used instead.

Programming languages are meant to be read as well as written, and someone relatively new to Python (and many who have used the language for a long time) is certain to get confused about the difference between:

   return [lambda x, i=i : i * x for i in range(5)]
and

   return [lambda x : i * x for i in range(5)]


Agreed 100%, this type of constructions should be avoided in the first place in favor of more "readable" ones but this happens in a fair amount of code that I've seen (and I keep seeing).


Some of it seems to come from people cargo-culting their knowledge of anonymous and first class functions, so they end up believing that the only way to pass a function around is to construct it anonymously.


In the particular case of constructing several similar functions that do essentially the same thing, lambda is a rather natural choice.

Being more explicit and less hacky can well be combined with staying true to functional style:

    from functools import partial
    
    mul = lambda x, y: x*y  # could use int.__mul__, too
    multipliers = [partial(mul, n) for n in range(5)]
It does the closure-capturing of n for you.


A function defined with def would work just the same there.

It would have a big ugly 'return' in it and be a few characters longer, but it would work the same, so I don't see what lambda brings to it.


Both def and lambda would fail identically in this context.




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