Let's say we want to write a most simple implementation 'avg' function: const avg = list => { let sum = 0; for(let i = 0; i < list.length; i++) { sum += list[i] } return sum / list.length } Basiclly, the 'avg' function doing two things: Calculate su…

柯里化相当于函数重构: 偏函数相当于函数适配. So, what is the difference between currying and partial application? As we stated before: Currying: Ability to decompose a function with arity N (where N is > 1) in a chain of calls to smaller functions with arity 1. Partial a…

An introduction to concatting items via the formal Semi-group interface. Semi-groups are simply a type with a concat method that are associative. We define three semigroup instances and see them in action. 1. What is Semigroups: Array type, String ty…

State is a lazy datatype and as such we can combine many simple transitions into one very complex one. This gives us a lot of control over how our state changes over time. In this lesson we will use this to our advantage and combine many transactions…

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…

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…

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…

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…

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…