what is a monoid

[dullbananas]

the documentation needs to explain what a monoid/semigroup is

[nikita-volkov]

Agreed. Care to PR?

[dullbananas]

no. i dont understand the concept of monoids and semigroups

[nikita-volkov]

Got it.

Until we add the docs I suggest to check out the Haskell or PureScript docs on those concepts:

• https://pursuit.purescript.org/packages/purescript-prelude/3.0.0/docs/Data.Semigroup#t:Semigroup
• https://pursuit.purescript.org/packages/purescript-monoid/3.0.0/docs/Data.Monoid#t:Monoid

[dullbananas]

is it basically something that has andThen?

[nikita-volkov]

That would be Monad :)

Monoid is a binary operation (function on two arguments) equipped with identity value (a neutral value in regards to the binary operation). Here's a few examples of practical monoids:

• string concatenation for binary operation and empty string for identity value
• numeric sum for binary operation and 0 for identity value
• numeric product for binary operation and 1 for identity value
• list concatenation and empty list
• command batching and empty command.

This is an extremely universal abstraction and it allows you to apply the same patterns in composition of seemingly completely unrelated things.