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A comment on Not Lisp again (2009). Parent comment

Re:Not Lisp again (2009) by AnimalMuppet on Tuesday May 02, 2017 @01:52PM (#14248747)
OK, for the example given, I don't see how closures are relevant. I could write the exact same derivative function in C in 1983.

Are you saying that in general, closures are essential to first-class functions? Or are you saying that, in the derivative example, there's something going on with closures?

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Re:Not Lisp again (2009) by phailhaus on Tuesday May 02, 2017 @02:17PM (#14249035)
Are you sure? Because in the example given, it seems that the inner function needs access to the function f
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Re:Not Lisp again (2009) by AnimalMuppet on Tuesday May 02, 2017 @04:18PM (#14250172)
See smitherfield's examples. Yes, the inner function needs access to f. This means that it has to be passed in to the inner function. But in my view, that's not any different than (in the original example) having deriv-cube calling deriv with cube as an argument (or composing deriv and cube, if you prefer).

You may say that the difference is that in Lisp, deriv-cube is a partial application, whereas in C you really can't do that. And you'd be right. But for this example, I don't see what difference it makes.

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