We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is Functional Programming?

By D. Poupon
Updated May 16, 2024
Our promise to you
EasyTechJunkie is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At EasyTechJunkie, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Functional programming is a programming paradigm where the base of computation is the evaluation of expressions. Some characteristics are the use of higher-order functions, referential transparency and lazy evaluation. The advantages of the programming style include that programs are easy to read, are very reliable and can be broken into components. Disadvantages are that computations may be slow and the style and syntax are completely different from other common programming styles. The functional programming style is more often embraced by academics than by computer science professionals.

As the name suggests, functions are a fundamental part of this programming paradigm. Functions may be nested within other functions, called higher order functions, and each higher-order function can be broken down into building block functions that are easy to understand and debug. Examples of some higher order functions are Map and Nest. The function Map takes a function F and the list of variables, for instance (x, y, z) and gives the result in a list: Map [F, (x, y, z)] = (F(x), F(y), F(z)). Nest takes the function F, the variable x, and the number of iterations: Nest[ F, x, 3] = F(F(F(x))).

Pure functional programming takes an input and returns an output without ever changing a variable’s state. In other words, a function with the same input will always give the same results regardless of what has occurred previously in the program. This is called referential transparency. Since mathematical functions are referentially transparent, functional programming is intuitive to many mathematicians, engineers and scientists.

The referential transparency of functions means that the order of function evaluation is not important. Therefore functions need not be evaluated until their results are needed, which is called lazy evaluation. This is in complete contrast with imperative programming, where a program begins with the first command and runs through the list until the last command. Lazy evaluation skips over parts of the program that do not follow logically or are superfluous, which automatically optimizes the program and may reduce computing time.

Functional programming has many advantages over other programming paradigms. Functions with clear inputs and outputs are easy to read and understand. Once a function is thoroughly debugged, it can be reliably used in other applications. Multicore machines may be able to compute functions that are evaluated independently in parallel, drastically improving the performance of programs.

Unfortunately, not all programs lend themselves to parallel computing, and computing functional programs may be rather slow. Functional programs rely heavily on recursion, which is often less efficient that using traditional loops or iteration methods. In fact, functional programming can be quite clumsy and difficult to learn since it does not resemble other more common paradigms such as object oriented programming.

Academics tend to favor functional programming since it provides a clear and understandable way to program complex real world problems. Some pure languages are Haskell and Erlang. Mathematica is specialized in symbolic mathematics, R is specialized in statistics and J is specialized in financial analysis. Multiparadigm languages such as Scala and F# supports both functional programming and other programming styles.

EasyTechJunkie is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.

Discussion Comments

EasyTechJunkie, in your inbox

Our latest articles, guides, and more, delivered daily.

EasyTechJunkie, in your inbox

Our latest articles, guides, and more, delivered daily.