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Introduction to JavaScript

bookDefining Functions in JavaScript

To create a new function, use the function keyword. Provide a name for the function and define any arguments it should accept:

function functionName(arguments) {
  // code block
}

The structure of a function definition includes:

  • The function keyword;
  • The function name, typically in camelCase like variables;
  • Arguments enclosed in parentheses ();
  • A code block within curly brackets {}.

Arguments

Functions have their own data storage space. Arguments are values passed to a function, which the function uses as variables. These arguments cease to exist when the function finishes executing.

To define arguments, assign a name to each one:

// Function without arguments
function first() {}

// Function with one argument
function second(argument) {}

// Function with multiple arguments
function third(argument1, argument2, argument3) {}

If a function accepts multiple arguments, separate them with commas (,).

Note

Arguments are used like variables inside the function's code block.

Function calling

To use a function, call it using parentheses () and provide the necessary arguments if the function expects any:


              
1234567891011

            
// Function Definition
function func(arg) {
  console.log("Argument received:", arg);
  console.log("Argument type:", typeof arg);
}

// Function Calling
func(1);
func(2521);
func("Rabbit");
func(true);
copy
question mark

Which of the following correctly defines a function that takes two arguments?

Select the correct answer

Everything was clear?

How can we improve it?

Thanks for your feedback!

SectionΒ 6. ChapterΒ 2

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bookDefining Functions in JavaScript

Swipe to show menu

To create a new function, use the function keyword. Provide a name for the function and define any arguments it should accept:

function functionName(arguments) {
  // code block
}

The structure of a function definition includes:

  • The function keyword;
  • The function name, typically in camelCase like variables;
  • Arguments enclosed in parentheses ();
  • A code block within curly brackets {}.

Arguments

Functions have their own data storage space. Arguments are values passed to a function, which the function uses as variables. These arguments cease to exist when the function finishes executing.

To define arguments, assign a name to each one:

// Function without arguments
function first() {}

// Function with one argument
function second(argument) {}

// Function with multiple arguments
function third(argument1, argument2, argument3) {}

If a function accepts multiple arguments, separate them with commas (,).

Note

Arguments are used like variables inside the function's code block.

Function calling

To use a function, call it using parentheses () and provide the necessary arguments if the function expects any:


              
1234567891011

            
// Function Definition
function func(arg) {
  console.log("Argument received:", arg);
  console.log("Argument type:", typeof arg);
}

// Function Calling
func(1);
func(2521);
func("Rabbit");
func(true);
copy
question mark

Which of the following correctly defines a function that takes two arguments?

Select the correct answer

Everything was clear?

How can we improve it?

Thanks for your feedback!

SectionΒ 6. ChapterΒ 2
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