Functional languages use a different paradigm than imperative and object-oriented languages. They use side-effect-free functions as a basic building block in the language. This enables lots of things and makes a lot of things more difficult (or in most cases different from what people are used to). One of the biggest advantages with functional programming … Read more
Algebras I think the place to start would be to understand the idea of an algebra. This is just a generalization of algebraic structures like groups, rings, monoids and so on. Most of the time, these things are introduced in terms of sets, but since we’re among friends, I’ll talk about Haskell types instead. (I … Read more
You can read about the changes in What’s New In Python 3.0. You should read it thoroughly when you move from 2.x to 3.x since a lot has been changed. The whole answer here are quotes from the documentation. Views And Iterators Instead Of Lists Some well-known APIs no longer return lists: […] map() and … Read more
According to Pippenger [1996], when comparing a Lisp system that is purely functional (and has strict evaluation semantics, not lazy) to one that can mutate data, an algorithm written for the impure Lisp that runs in O(n) can be translated to an algorithm in the pure Lisp that runs in O(n log n) time (based … Read more
The Haskell approach seems to be to just wrap imperative GUI toolkits (such as GTK+ or wxWidgets) and to use “do” blocks to simulate an imperative style That’s not really the “Haskell approach” — that’s just how you bind to imperative GUI toolkits most directly — via an imperative interface. Haskell just happens to have … Read more
A Y-combinator is a “functional” (a function that operates on other functions) that enables recursion, when you can’t refer to the function from within itself. In computer-science theory, it generalizes recursion, abstracting its implementation, and thereby separating it from the actual work of the function in question. The benefit of not needing a compile-time name … Read more
Case classes can be seen as plain and immutable data-holding objects that should exclusively depend on their constructor arguments. This functional concept allows us to use a compact initialization syntax (Node(1, Leaf(2), None))) decompose them using pattern matching have equality comparisons implicitly defined In combination with inheritance, case classes are used to mimic algebraic datatypes. … Read more
You will be able to get the current iteration’s index for the map method through its 2nd parameter. Example: const list = [ ‘h’, ‘e’, ‘l’, ‘l’, ‘o’]; list.map((currElement, index) => { console.log(“The current iteration is: ” + index); console.log(“The current element is: ” + currElement); console.log(“\n”); return currElement; //equivalent to list[index] }); Output: The … Read more
Variable scope When you declare a local variable, that variable has a scope. Generally, local variables exist only within the block or function in which you declare them. function() { var a = 1; console.log(a); // works } console.log(a); // fails If I try to access a local variable, most languages will look for it … Read more
What are some common uses for this language? Rapid application development. If you want to know “why Haskell?”, then you need to consider advantages of functional programming languages (taken from https://c2.com/cgi/wiki?AdvantagesOfFunctionalProgramming): Functional programs tend to be much more terse than their ImperativeLanguage counterparts. Often this leads to enhanced programmer productivity FP encourages quick prototyping. As … Read more