Function - First Class Function (Closure|Function Literal)

Model Funny


A programming language is said to support first-class functions if it treats functions as first-class objects.

The language supports:

  • constructing new functions during the execution of a program,
  • storing them in variable,
  • passing them as arguments to other functions,
  • and returning them as the values of other functions.

Resumed: you can return an inner function to be called sometime later on.

first-class functions are also known as:

A closure is a block of code that can be passed as an argument to a function. You can define a block of code and pass it around as if it were a string or an integer.

A closure is a variable storing:

A closure can continue to access a function’s scope (its variables) even once the function has finished running.

A closure is a callback function that can see non-local variables in the location where they were defined.

Closures are finding their way into many major languages, such as Java, C#, and PHP.


The function values contain then:

  • the code required to execute when they’re called.
  • and any variables pointer they may refer

Functions that keep track of variables from their containing scopes are known as closures.


A first class function (closure) that creates a context and retains its state.

function makeCounter() {
  var i = 0;

  return function() {
    console.log( ++i );

var counter = makeCounter();

Documentation / Reference

Recommended Pages
Bash Liste Des Attaques Ovh
Bash - Function

A shell function is an object that: is called like a simple command and executes a compound command with a new set of positional parameters. By convention, the function name starts with an underscore....
Card Puncher Data Processing
Groovy - Closure

in Groovy
Java Conceptuel Diagram
Java - lambda expressions

A lambda expression is a litteral expression that implements a functional interface (interface with only one method). Because a functional interface contains only one abstract method, a lambda expression...
Javascript - Closure

Closure in Javascript The most common usage of closure in JavaScript is the module pattern. Closures have access and can update their outer variables. Closures store their outer variables by references,...
Javascript Function Method
Javascript - Functions

Functions functionalities in Javascript. A function in Javascript is a variable that’s given a reference to the function being declared. The function itself is a value (as an integer or an array) that...
Card Puncher Data Processing
Language - First class-citizen

A first-class citizen is an entity which supports all the operations generally available to other entities. These operations typically include: being passed as an argument, returned from a function,...
Card Puncher Data Processing
PySpark - Closure

Spark automatically creates closures: for functions that run on RDDs at workers, and for any global variables that are used by those workers. One closure is send per worker for every task. closures...

Share this page:
Follow us:
Task Runner