Contents
- Sequencing with effects
- Revisiting Validation
- Exercise 1
- Exercise 1, Part 2
- Discarding results
- Parsing
- Exercise 2
- Coming up
Previously we looked at the connection between <*>
and liftA2
, their connection to fmap
, the pure
function, and the monoidal structure of applicatives. We will still want to give some closeup attention to a few other applicatives, especially functions and lists, but this lesson will focus on the other operators in the typeclass (<*
and *>
) before we move on to those. While you almost never need to implement them yourself – because the compiler can derive them from your implementations of pure
and <*>
(or pure
and liftA2
) – they are useful, yet often ignored. They are useful enough to deserve at least one lesson of their own.