Injectivity of pure

Stream: new members

[Yakov Pechersky]

Is there an example of a lawful applicative such that pure is not injective?

[Mario Carneiro]

const

[Mario Carneiro]

that is, pure a = ()

[Yakov Pechersky]

But for all non subsingleton ones, is it true?

[Mario Carneiro]

Any monoid can be used to build a const applicative where you ignore the thing you were passed

[Adam Topaz]

The world has many many many MANY monads....