Functional Programming Languages

What Is A Functional Programming Language?

Functional programming involves writing code in pure functions. It is a declarative programming paradigm where function definitions are trees of expression that map values to other values. It is opposite to the imperative paradigm where the sequence of statements can update the running state of the program.

What is Functional Programming?

Generally, functional programming means using functions to the best effect for creating clean and maintainable software. More specifically, functional programming is a set of approaches to coding, usually described as a programming paradigm.

Functional Programming VS OOPS

• Definition: Functional programming emphasizes on evaluation of functions. Object-oriented programming is based on concepts of object.
• Data: Functional programming uses immutable data. Object-oriented programming uses mutable data.
• Model: Functional programming follows declarative programming model. Object-oriented programming follows imperative programming model.
• Support: Functional programming supports parallel programming. Object-oriented programming does not support parallel programming.
• Execution: In functional programming the statements can be executed in any order. In object-oriented programming the statements need to be executed in a particular order.
• Iteration: In functional programming recursion is used for iterative data. In Object-oriented programming loops are used for iterative data.
• Element: The basic elements of functional programming are functions and variables. In object-oriented programming the basic elements are objects and methods.
• Use: Functional programming is used only when there are few things with more operations. Object-oriented programming is used when there are many things with few operations.

Advantages of Functional programming

• Shorter code
• Easy debugging
• Modular
• Parallel programming
• Increased maintainability
• Code readability

Functional Programming Languages To Learn

• Elixir: It is a functional, general-purpose, and concurrent programming language that runs on the BEAM virtual machine. It is popular for its suitability to build low-latency, fault-tolerant, and distributed applications.
• Erlang: Erlang is used to code WhatsApp. Erlang is a general-purpose, concurrent, functional programming language, and garbage-collected runtime system. It is specifically designed for concurrency, distribution, and fault tolerance. It is suitable for building distributed, real-time, and concurrent systems such as telecommunications, database applications, servers, and highly-available systems.
• Common Lisp: Common Lisp is a dialect of the Lisp programming language. It is a general-purpose, dynamic, and multi-paradigm language that supports a combination of procedural, functional, and object-oriented programming styles. Lisp is one of the oldest programming languages and there are many dialects of Lisp that have existed over time.
• Haskell: Haskell is considered the ‘mother’ of all functional programming languages. Haskell is a general-purpose, statistically typed, and purely functional programming language offering type inference and lazy evaluation. It is older than Java and became a pathfinder for many advanced features in programming languages.
• F#: F# is a general-purpose, functional-first, strongly-typed, and multi-paradigm programming language that consists of functional, imperative, and object-oriented methods. It is most often used as a cross-platform (Common Language Infrastructure) CLI language on .NET. It is similar to OCaml with few differences.
• Clojure: Clojure is a popular dynamic and functional dialect of the Lisp programming language on the Java platform. Clojure features immutable and persistent data structures and also allows developers to manage identity and states explicitly. This gives developers a big advantage to create concurrent and fast programs.
• Elm: Elm is a domain-specific programming language specifically used for building web browser-based GUIs. It is a purely functional language and offers usability, simplicity, performance, and robustness. Elm compiles to JavaScript. Some noticeable features of this language include no runtime exceptions, easy refactoring, friendly error messages, great performance, module system, static typing, and interoperability with HTML, CSS, and JavaScript.
• Racket: Racket is a dialect of Lisp and a descendent of the Scheme. Racket is a modern, general-purpose, multi-paradigm programming language and a multi-platform distribution that includes the language itself, standard library, IDE, development tools, and a set of additional languages.
• OCaml: Ocaml, Objective Caml is a general-purpose, multi-paradigm language that extends the Caml dialect of ML with object-oriented features. It is a free and open-source project managed and maintained by the French Institute for Research in Computer Science and Automation.
• Idris: Idris is yet another purely-functional programming language. It offers many features borrowed from mainstream functional programming and proof assistants. The key features of Idris include dependent types, lazy evaluation, and totality checker. It encourages Type-Driven Development where types are tools for creating programs.
• PureScript: PureScript is a strongly-typed and purely-functional programming language that compiles to JavaScript. Syntactically, it is similar to Haskell. It has also a set of great features such as persistent data structures, pattern matching, type classes, and functional dependencies, and higher-rank polymorphism.
• Wolfram: Wolfram language is a general, multi-paradigm programming language developed by Wolfram Research. It emphasizes functional programming, rule-based programming, and symbolic computation. It was a part of the initial version of Mathematica in 1988.
• Scala: Scala is not functional but it supports functional programming and object-oriented programming. The reason we consider Scala for functional programming is, it combines OOP and functional programming in one concise, high-level language.
• Python: Python doesn’t need any introduction. It is not functional language but it supports coding in a functional, declarative style. Its design offers support for functional programming through functions, generator expressions, list comprehensions, sets, and dictionaries. It is inspired by Haskell and Standard ML.
• Kotlin: Kotlin is a cross-platform, statically typed, and general-purpose programming language but it can be used to code in functional styles. It is a great choice for exploring functional programming as it offers first-class support for features such as function types and lambdas, higher-order functions, and many more.
• JavaScript: JS is high-level, often just-in-time compiled, and multi-paradigm. It supports dynamic typing, first-class functions, and prototype-based object orientation. JavaScript is one of the core technologies of the World Wide Web along with CSS and HTML. Being a multi-paradigm language, it supports event-driven, functional, and imperative programming styles.