Gain insights into Haskell's functional programming by learning to write pure functions, use pattern matching, recursion, and Lists, define data types, and execute IO operations.

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Functional programming is a problem-solving paradigm that differs drastically from the imperative programming style of languages like C++ or Java. While functional programming principles have invaded most modern programming languages to some degree, there is no language that embraces this paradigm quite as Haskell does. As a result, Haskell code can reach a level of expressiveness, safety, and elegance that is difficult to achieve in other programming languages.

This course will introduce you to the core concepts of functional programming in Haskell. You will learn how to write pure functions using techniques such as pattern matching and recursion, and how to work with Haskell's powerful List data type. You will understand the basics of Haskell's powerful type system and define your own data types. Finally, you’ll learn how to perform IO operations the Haskell way. By the end of this course, you’ll have a new paradigm to add under your belt and you can start using functional programming in your own projects.

Learn Functional Programming in Haskell

Let's continue discovering some of the syntactic sugar that Haskell offers us. In this lesson, we focus on bindings for subexpressions.

Sometimes when writing functions, the expressions on the right hand side of equations can become quite complex, especially when they involve repeated subexpressions. For example, consider the task to write a function which solves the quadratic equation 

$$x^2 + px + q = 0$$

We know that this equation has solutions as long as

$$\left(\frac{p}{2}\right)^2 - q \geq 0$$

and these solutions are equal to 

$$-\frac{p}{2} \pm \sqrt{\left(\frac{p}{2}\right)^2 - q}$$

Let's translate this into a Haskell function, ignoring for now the case where there are no solutions.

Learn how to split complex expressions into reusable subexpressions.

Introduction

First Steps with Haskell

Techniques for Writing Functions

Working with Lists

Creating Data Types

Input and Output

Conclusion

Appendix

Syntactic Sugar II: let and where