The fmap laws are not redundant when you have free theorems. Both views are correct and in Haskell, equivalent. If you're wondering how modularity in various dialects and expressions of ML differ from the kind of modularity you see in Haskell, this might help. I refuse to write another Monad tutorial (I'm not knowledgeable enough) but I'll write about what I've understood so far. Fluokitten: Learn You a Haskell for Great Good - in Clojure. Learn You a Haskell for Great Good! Please help update and extend it by editing it yourself or by leaving comments, suggestions, and questions on the talk page. Just what is functional programming? I refuse to write another Monad tutorial (I'm not knowledgeable enough) but I'll write about what I've understood so far. is a fun, illustrated guide to learning Haskell, a functional programming language that's growing in popularity. Simple enough. Quickly Learn You a Haskell for Great Good! While some of them, such as the "number classes" hierarchy, can be justified by pragmatism or lack of a strictly better suggestion, there is one thing that stood out as, well, not that: Applicative not being a superclass of Monad. This is the idea that Functors, Applicatives, Monads, Arrows etc are all based on. Or if you just want a quick intro into applicative vs. generative functors, module and type sharing constraints, and recursive modules in ML. and it has a very good explanation of Functors, Applicative Functors, and Monads. A Maybe implements all three, so it is a functor, an applicative, and a monad. This is now the official version of the Typeclassopedia and supersedes the version published in the Monad.Reader. ... start up Clojure REPL and open this article and the Learn You a Haskell for Great Good book side by side and we are ready to go. book. I'm currently reading "Learn You a Haskell for Great Good" (really great book, if you want to learn Haskell, you can read it online or better, buy it now!) We asked a member of the team that created Haskell: John Hughes, Professor of Computer Science at Chalmers University of … A functor is a data type that implements the Functor typeclass. The day-to-day differences in uses of Functor, Applicative and Monad follow from what the types of those three mapping functions allow you to do. That's why there's a Simple Haskell movement now, calling on devs to publish more intro-level code in the language and facilitate more progress on the part of newbies. INDEX) > / / INDEX <-using IO functions and < According to Haskell and the Fantasy Land specification, a functor is simply something that can be mapped over.In OOP-speak, we’d call it a ‘Mappable’ instead. If you've never written any Haskell before, download out Getting Started Checklist! introduces programmers familiar with imperative languages (such as C++, Java, or Python) to the unique aspects of functional programming. I'm currently reading "Learn You a Haskell for Great Good" (really great book, if you want to learn Haskell, you can read it online or better, buy it now!)