Lifting Now, let's review map from another perspective. map :: (T -> R) -> [T] -> [R] accepts 2 parameters, a function f :: T -> R and a list list :: [T]. [T] is a generic type paramterized by T, it's not the same as T, but definitely shares s…
Functions in Java Prior to the introduction of Lambda Expressions feature in version 8, Java had long been known as a purely object-oriented programming language. "Everything is an Object" is the philosophy deep in the language design. Objects a…
In computer science, functional programming is a programming paradigm, a style of building the structure and elements of computer programs, that treats computation as the evaluation of mathematical functions and avoids state and mutable data. It is a…
It is really important to understand function signature in functional programming. The the code example below: const map = fn => anyFunctor => anyFunctor.map(fn); 'map' is pointfree version of any founctor's map, for example: Maybe.of('maybe').map(t…
1. Functional programming treats computation as the evaluation of mathematical and avoids state and mutable data. Scala encourages an expression-oriented programming(EOP) 1) In expression-oriented programming every statement is an expression. A state…
background In pursuit of a real-world application, let’s say we need an e-commerce web applicationfor a mail-order coffee bean company. They sell several types of coffee and in differentquantities, both of which affect the price. Imperative methods F…
A functional programming function is like a mathematical function, which produces an output that typically depends only on its arguments. Each time a functional programming function is called with the same arguments, the same result is achieved. Func…
In this blog post I will talk about the changes coming in Angular 2 that will improve its support for functional programming. Angular 2 is still in active development, so all the examples are WIP. Please focus on the capabilities and ideas, and not t…
In functional programming, a monad is a design pattern that defines how functions, actions, inputs, and outputs can be used together to build generic types,[1] with the following organization: Define a data type, and how values of that data type are…
What is Arrow Functor? Arrow is a Profunctor that lifts a function of type a -> b and allows for lazy execution of the function. Arrow can be considered a Strong Profunctorif the underlying data running through the Arrow is a Pair, typically in the f…
A pointed functor is a functor with an of method class IO { // The value we take for IO is always a function! static of (x) { return new IO(() => x) } constructor (fn) { this.$value = fn; } map (fn) { return new IO(compose(fn, this.$value)) } } What'…
We will see a peculiar example of a pure function. This function contained a side-effect, but we dubbed it pure by wrapping its action in another function. Here's another example of this: // getFromStorage :: String -> (_ -> String) const getFromSto…
What is applicative functor: the ability to apply functors to each other. For example we have tow functors: Container(2), Container(3) // We can't do this because the numbers are bottled up. add(Container.of(), Container.of()); // NaN We cannot just…
Link:http://refactoring.info/tools/LambdaFicator/ Problem Description Java 8 will support lambda expressions and will extend the Collections APIs with functional operations like map or filter that apply a lambda expression over the elements of a coll…
When combining multiple State ADT instances that depend on the same input, using chain can become quite burdensome. We end up having to play leapfrog with values inside of nested chain statements. Very reminiscent of the old callback nastiness we had…
In previous post, Arrow Functor with contramap, we have seen how to opreating on params before we invoke the function by using Arrow + contramap. It happens before function get inovked, before we get result. We can say this opreation happens on the l…
This post is similar to previous post. The difference is in this post, we are going to see how to handle both successfuly result and error result by using Pair functor. So, still we have our funs.js: which is the same as previous post. const fs = req…
Let's say we are going to read some files, return the first file which pass the prediction method, this prediction method can be just check whether the file content contains more than 50 chars. For reading the file, it has tow requirements, first we…
Let's examine a pointfree way to write these applicative calls. Since we know map is equal to of/ap, we can write generic functions that will ap as many times as we specify: const liftA2 = curry((g, f1, f2) => f1.map(g).ap(f2)); const liftA3 = curry(…
