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Comment by greenkey | Hacker News Reader

> That said, Common Lisp is weird. What I find particularly jarring is that functions and variables live in different namespaces: if you put a function into a variable, you can’t just use it like a function, you have to funcall it.

Unless I’m misunderstanding, the author sounds like a developer that’s primarily used JS. It’s really not abnormal to have to include parens after a method name in a language, which indicating that you are calling a function.

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> It’s really not abnormal to have to include parens after a method name in a language

That's not what he means. Assuming some pseudocode with a more common syntax to prune the parentheses question, Common lisp is doing this:

    function f(x) { print(x) }
    let a = f
    funcall(a)(27)  # prints 27

Whereas Scheme is doing this:

    function f(x) { print(x) }
    let a = f
    a(27)           # also prints 27

This is the fundamental difference between so-called Lisp-1 and Lisp-2 families, depending on whether functions and variable share the same namespace or if they have to be “lifted” from one to another through funcall.

I think you are misunderstanding.

In common Lisp you can call a regular function defined with defun as (foo "something"), but if bar is a variable containing a fuction you have to use (funcall bar " something"). I agree that this is weird and confusing.

Isn't that the same thing as using function pointers in C?

You need the * to access the function the variable points to.

Sure, this isn't that rare of a thing for languages, but it is increasingly rare to find people who think this is a good idea.

No you don't. You call the pointer itself. It points to the first instruction in the function.

It's more like Ruby's method(:foo) and .call().

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