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




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.


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 */ ;

// [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)
else if (two)
else if (three)
  ; // nothing here
else if (four)


Browser compatibility

BCD tables only load in the browser

See also