Snippets tagged state monad

  • Monadic state lifting combinators

    The generic model for stateful computation (S -> S x R) provides a convenient mechanism of threading stateful computation results since the functor λR . S -> S x R is monadic. But what happens if we want to thread state itself? Well, the mapping λS. S -> S x R is not even functorial! But it turns out it can become so with a bit of trickery. This snippet demonstrates a way to lift, project or inject stateful computations into ambient state monads.

    8 people like this

    Posted: 6 years ago by Eirik Tsarpalis

  • Update Monad in F# based on Tomas Petricek article

    This is 100% based on tomas petricek blog article. there has been some small additions in regards to adding Result type and handling Monoids for the Writer Part. go check the following blog article : http://tomasp.net/blog/2014/update-monads/ Comment appreciated + bear in mind that performance wise, the Monoid Combine operator, could be greatly improved and more.

    3 people like this

    Posted: 6 months ago by Fahd Abdeljallal