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Comment by flavio81 | Hacker News Reader

Yes but lambda allows some versatility, for example (excuse my Python, it is a bit rusty):

    formulas = {
        'sum': lambda x,y: x+y,
        'subst': lambda x,y: x-y,
        'mult': lambda x,y: x*y,
        'pow': lambda x,y: x**y
        }

    def apply_operator(operation_name, x, y):
        operation=formulas[operation_name]
        return operation(x,y)

Using "def"s there would kill readability and easiness of coding.

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Bad example :)

Most simple uses of lambda like this can be substituted with functions from the operator module:

  import operator

  formulas = {
    'sum': operator.add,
    'subst': operator.sub,
    'mult': operator.mul,
    'pow': operator.pow
  }

I thank you for this example. If the operator definitions are not trivial and you want to keep them well mantained, then your example is very good.

However, what I meant was that for fast, quick coding, if your 'operator' function is really simple, then lambda fints perfectlu.

I know the Zen of Python says: "There should be one—and preferably only one—obvious way to do it", but i don't align to that principle. I think there should be more than one way to do something, and one should choose one that fits the best.

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