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Comment by runarberg | Hacker News Reader

Just came back to python after several years in javascript. I've found that the functions you need are often already provided in the standard library (for example the `operator` module[1]).

So where in javascript you would write:

    const double = x => x * 2

In python you can simply write:

    from operator import mul
    double = mul(2)

[1]: https://docs.python.org/2/library/operator.html

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The Python equivalent of your JavaScript example is simply:

    def double(x): return x * 2

Python's `lambda` construct creates anonymous functions - its limitations mean it should only be used when anonymity is required. If a function is to be given a name, there is no reason to use a lambda over standard function syntax.

That won't work, you have to use something like partial instead if you want to use the operator module:

    from functools import partial
    import operator
    double = partial(operator.mul, 2)

And at that point I think it would way simpler to just define a normal function.

That don't work since you need to use `partial` on `mul`.

I'm a big fan of the way Haskell manages operators and partial application.

    double :: Num a => a -> a
    double = (2 *)

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