Mastering Functional Programming

ProductR

Before diving deep into the library and discussing its features, we need to mention a particular operator that is frequently used throughout this library. We have already discussed the Applicative type class, and that it is useful for parallel composition.

An operator from this type class that is frequently used in cats is a so-called right product operator.

The operator in question takes two computations, performs a product between them, and takes only the right-hand result. Particularly in the Cats effect, the operator is frequently used to specify that one event should happen after another.

It also has a symbolic form, which looks like this: *>.