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A comment on Functor, Applicative, and Monad. Parent comment

Re:Functor, Applicative, and Monad by _bxg1 on Wednesday September 18, 2019 @06:36PM (#21011148)
As someone who's only spent about an hour reading an intro to Haskell (and none reading about OCaml), I was able to mostly get the gist of what was being said. Not completely. I had to look up the * operator (effectively a comma between arguments, as opposed to a currying arrow), but I would consider the article to have been useful, even if it could've been more useful.
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Re:Functor, Applicative, and Monad by TheAsprngHacker on Thursday September 19, 2019 @01:58AM (#21013677)
The OCaml type 'a * 'b is the equivalent of the Haskell type (a, b). This type is known as the Cartesian product type, and it's written with a multiplication symbol in type theory (hence the asterisk in OCaml syntax).

The product type is the type of pairs. It's definition is

    x : A
    y : B
    --------------
    (x, y) : A * B
meaning that if x has type A and y has type B, then (x, y) has type A * B.

- Product type on Wikipedia: https://en.wikipedia.org/wiki/Product_type - Product type on the nLab (which is a math-heavy resource): https://ncatlab.org/nlab/show/product+type

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