Web/JavaScript/Reference/statements/empty-2

An empty statement is used to provide no statement, although the JavaScript syntax would expect one.

Syntax

Description

The empty statement is a semicolon (;) indicating that no statement will be executed, even if JavaScript syntax requires one.

The opposite behavior, where you want multiple statements, but JavaScript only allows a single one, is possible using a block statement, which combines several statements into a single one.

Examples

Empty loop body

The empty statement is sometimes used with loop statements. See the following example with an empty loop body:

let arr = [1, 2, 3];

// Assign all array values to 0
for (let i = 0; i < arr.length; arr[i++] = 0) /* empty statement */ ;

console.log(arr);
// [0, 0, 0]

Unintentional usage

It is a good idea to comment intentional use of the empty statement, as it is not really obvious to distinguish from a normal semicolon.

In the following example, the usage is probably not intentional:

if (condition);       // Caution, this "if" does nothing!
   killTheUniverse()  // So this always gets executed!!!

In the next example, an if...else statement without curly braces ({}) is used.

If three is true, nothing will happen, four does not matter, and also the launchRocket() function in the else case will not be executed.

if (one)
  doOne();
else if (two)
  doTwo();
else if (three)
  ; // nothing here
else if (four)
  doFour();
else
  launchRocket();

Specifications

Specification
ECMAScript (ECMA-262)The definition of 'Empty statement' in that specification.

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile						Server
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet	Node.js
Empty statement (`;`)	Chrome Full support 3	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 5	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 4.2	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100

Legend

Full support: Full support