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by catnaroek 3499 days ago
Most languages only have higher-order procedures, not higher-order functions.

As for closures, well, closures are an implementation technique. Not distinguishing between language features and implementation techniques is a part of an established tradition that comes from Lisp, but that doesn't make it any less wrong.
1 comments
frankpf 3499 days ago
> Most languages only have higher-order procedures, not higher-order functions.

What do you mean by that?

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catnaroek 3499 days ago
Functions have the following properties:

(0) A function maps every element of its domain to a unique element of its codomain.

(1) Functions don't exist in time, let alone change over time.

(2) Two functions with the same domain and codomain are equal if they map the same domain elements to the same codomain elements.

Since when do so-called “first-class functions” in most programming languages behave like this?

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