From the hub, written by: "Paul Brown"

Basic Idea of Recursion

Want to do something a bunch of times in Prolog? Recursion is how we do it. In this post we'll look at the most basic ideas of recursion and talk through a couple of examples.


Facts and Fluents vs Constants and Variables

In Prolog we have facts rather than constants, fluents rather than variables. This post is another terminology breakdown with examples and comparison to features common in other programing languages.


Predicates vs Functions

People from other languages often get a little confused with these predicate things, especially as their syntax looks similar to functions in other languages. In this post we contrast predicates and functions and demonstrate the advantage of using predicates over functions.


Partial Predicates

Did you know you can call partial predicates with arguments added later on? This is how many of the higher order predicates like `maplist` work. But you can take advantage of this too! Let's take a look at `call`.


Homoiconic Prolog: Explain yourself!

Prolog is rather popular for Expert Systems. Why? Well because it's homoiconic and because we have DCG's, we can reify a query to make it explain itself. That's a lot of jargon, in this post we'll break it down and make some explanations.


Difference Lists Explored

Difference Lists are a very powerful and useful tool. They're also difficult to understand and can result in difficult to read code. In this post we'll address both of these issues.


Functional Prolog: Map, Filter and Reduce

Prolog programs have both logical and procedural meanings. In this post we'll take a look at procedural ideas more commonly associated with functional programming than Prolog, namely: map, filter and reduce (foldl and foldr). We'll code them and then query them.