Functieprogrammering

Functieprogrammering, also known as functional programming, is a programming paradigm that treats computation as the evaluation of mathematical functions and avoids changing-state and mutable data. It is a declarative programming paradigm, which means programming is done with expressions or declarations instead of statements. In functional code, the output value of a function depends only on the arguments that are input to the function, and not on any global state or side effects.

Key concepts in functional programming include first-class and higher-order functions, pure functions, immutability, and recursion. First-class functions are functions that can be passed as arguments to other functions, returned as values from other functions, and assigned to variables or stored in data structures. Higher-order functions are functions that take other functions as arguments or return them as results. Pure functions are functions that have no side effects and always produce the same output given the same input. Immutability refers to the inability to change the state of an object once it has been created. Recursion is a technique where a function calls itself to solve smaller instances of the same problem.

Functional programming languages include Haskell, Lisp, Erlang, and Scala. These languages provide built-in support for functional programming constructs and encourage functional programming practices. Functional programming is used in a variety of domains, including web development, data analysis, and scientific computing. It is valued for its ability to produce code that is concise, modular, and easy to reason about.