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Comment by hahahahhaah | Hacker News Reader

Arrays are objects (allocated memory and metadata if you will). The function is what takes the array and an int and returns an item.

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In Object Oriented programming, yes, arrays are objects and the functions are a property of another object that can perform instructions on the data of the Array Object.

Similarly in Lisp, (a list-oriented language) both functions and arrays are lists.

This article however is discussing Haskel, a Functional Language, which means they are both functions.

> Similarly in Lisp, (a list-oriented language) both functions and arrays are lists.

In which Lisp? Try this in Common Lisp and it won't work too well:

  (let ((array (make-array 20)))
    (car array))

What is the car of an array? An array in Lisp (since Lisp 1.5 at least, I haven't read earlier documentation) is an array, and not a list. It does not behave as a list in that you cannot construct it with cons, and you cannot deconstruct it with car or cdr.

To quote John McCarthy "Since data are list structures and programs are list structures, we can manipulate programs just like data."

Yes, I know most people consider it to be a functional language, and some variants like 'common lisp' make that more explicit, but the original concept was markedly different.

Yeah I guess a c++ programmer might say `std::array::operator[]` is a function (or method, whatever), just like `std::array::size` is. And that identifying the array with just one of those functions (or even the collection of all methods offered) is to miss the point -- not just contiguous indices, but contiguous storage. A red-black tree with added constraints is not an array.

TFA does allude to this. An "array indexing function" that just met the API could be implemented as an if-else chain, and would not be satisfactory.

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