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; it combines several statements into a single one.


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

var arr = [1, 2, 3];

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

// [0, 0, 0]

Note: It is a good idea to comment the intentional use of the empty statement, as it is not really obvious to distinguish between 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!!!

Another Example: An if...else statement without curly braces ({}). 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

Feature Chrome Edge Firefox Internet Explorer Opera Safari
Basic support Yes Yes Yes Yes Yes Yes
Feature Android webview Chrome for Android Edge mobile Firefox for Android Opera Android iOS Safari Samsung Internet
Basic support Yes Yes Yes Yes Yes Yes ?

See also

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