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nvader

I would pay good money for a comparison of type systems, delivered in the vein of Cow Economics.

In Self, you have a cow. You ask the cow to moo. It moos.

In Java, you have a cow. You construct a CowMooFactory to create an MooIpml. The MooImpl moos.

In Python, you have a cow. You ask it to moo. It quacks.

In C, you have a pointer to a cow. You ask it to moo. Segmentation fault (core dumped).

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In Haskell mooing is an impure side effect. It has to be handled with a special design pattern - which recursively generates further side effects, including an infinite number of online tutorials which fail to explain what it does.

This pattern is called a Moonad.

You mean https://github.com/moonad/Moonad ?

In ML, your value moos. It is inferred to be a cow.

In Ruby, your value moos. Could be a cow; might be a MooDuck. Do you really care?

In Assembly, there is no cow, no mooing, there's a bunch of places where parts of cows and moos may or may not be stored. It's up to you to pick the parts of the cows and moos in the correct order, then send the numbers representing the places where the cow and moo parts are stored to a magic box that interprets your sequence of numbers and puts the cow into the correct order after which you jump over to the cow and tickle its belly until it moos.

In ML, it's inferred if it might, in any potential future, moo.

So what's the difference between ruby and python?

During the Ruby's runtime the cow might get monkeypatched into a bat.

In Ruby, the cow moos automatically.

About 3 seconds, depending on how many cows you have. ;)

In Swift, if cow is a reference type you all share a cow that moos whoever asks, but if cow is a value type then you all have your own copy of a cow that only moos for you.

That doesn't make any sense.

Didn't think Python had duck typing...

What do you think "duck typing" is? Historically, it feels like I've mostly heard the term applied to Python.

Edited to add: Please don't take my question as rhetorical attack - it was intended as inquiry. There may be different definitions floating around.

Well, there we are. I don't know Python so, both jokingly and literally, I didn't know Python had duck typing.

In Rust, you have a Cow. It's smart and allows you to clone borrowed things, including things which can moo.

But only clones on write, which is a useful optimization.

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