It can be difficult to decide which programming paradigm or programming language to learn if you are just starting to learn how to code.
Functional programming is a good option if you are looking to learn a programming paradigm that is relevant to today’s tech landscape. Functional programming is a simpler, cleaner, and easier way to create code. It is also easier for you to test and maintain the code.
But what exactly is functional programming? Continue reading to learn more about functional programming, its benefits, and the most widely used functional programming languages.
What is Functional Programming?
Functional programming (FP), a method of software development that uses only functions to create maintainable code, is called functional programming. This is also known as building programs by applying and composing functionalities.
Functional programming leverages language support by using functions such as arguments, variables, and return values. This allows for elegant and clean code. Functional programming avoids shared states and uses immutable data. This contrasts with object-oriented programming (OOP), where mutable data is used and shared states are used.
Functional programming languages are more focused on expressions and declarations than on the execution of statements. Functions are treated as first-class citizens, meaning they can be passed as arguments, return to other functions, attach to names, and so on.
FP focuses only on the results and not the process. Iterations such as loop statements or conditional statements (e.g. If-Else), aren’t supported.
FP was born from the lambda calculator (l-calculus), a simple notation that Alonzo Church, a mathematician, developed in the 1930s for functions and applications. Many programming languages and dialects use a functional paradigm, such as Scheme, Common Lisp, (CL), and Elixir.
Many of the top programming languages today, including C#, JavaScript and PHP, support programming in a functional style.
In the next section, we will discuss the differences between pure and impure functional programming functions.
Pure Functional Programming
Purely functional programming refers to a subset within FP that treats all functions in FP as pure or deterministic functions.
The development of future state of a system in deterministic mathematical functions does not allow for randomness. Pure functions, on the other hand, have identical function return values for identical arguments. The function application has no side effects, i.e. it doesn’t modify state variables outside of its local environment.
When you insert code outside of your function, a side effect occurs. This can cause the function to not perform its task properly. In contrast, impure functions can have one or more side effects.
The following JavaScript code will allow you to see pure functions in action:
function updateMyAddress(newAddress)
updateMyAddress() does not require any external code to perform its tasks. It is a pure function.
Impure Functional Programming
This JavaScript code will allow you to see impure functions in action:
const myAddresses = “ChurchSt., CovingtonCross”;
function updateMyAddress(newAddress)
updateMyAddess() can be considered an impure function because it contains code (myAddress). This code alters an external state, which can have side effects for updateMyAddress()
Why Functional Programming is Important
FP is less popular than object-oriented programs, but it has seen a rise in popularity due to machine learning and big data. Functional programming is known for its ability to efficiently parallelize pure function calls. Functional programming makes it easier to create code for data analysis workflows or tasks.
Because of its pure nature, FP excels at machine learning and analysis of large data sets. Pure functions will always produce the same results with no external values.
Algorithms built using FP can quickly identify and correct errors. Many programmers and software engineers would prefer to work with a programming paradigm with pure functions that is simple to debug.
John Hughes, University of Glasgow, highlighted the importance of functional programming in future tech development due to its modularity. Modularity allows you to break down complex projects into smaller modules. The modules can be tested separately, which reduces the time required for unit testing and debugging.
“Functional programming languages offer two types of glue: lazy evaluation and higher-order functions. Hughes notes that these glues allow one to modularize programs in new and more useful ways.” Hughes wrote in his paper.
Functional Programming’s Advantages
Modularity – Functional programming is highly modular, as we have already mentioned. This makes the code easier to read and reduces its size. Anyone who has tried it knows how to do it.
What is Functional Programming? Why use it?
