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The empty statement is a semicolon (
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]
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!!!
if...else statement without curly braces (
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();
|ECMAScript Latest Draft (ECMA-262)
The definition of 'Empty statement' in that specification.
|Empty statement (||Chrome Full support 3||Edge Full support 12||Firefox Full support 1||IE Full support 3||Opera Full support Yes||Safari Full support 5||WebView Android Full support 1||Chrome Android Full support 18||Firefox Android Full support 4||Opera Android Full support Yes||Safari iOS Full support 4.2||Samsung Internet Android Full support 1.0||nodejs Full support Yes|
- Full support
- Full support