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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!!!
In the next example, an
statement without curly braces (
) is used.
, nothing will happen,
does not matter, and also the
function in the
case will not be executed.
if (one) doOne(); else if (two) doTwo(); else if (three) ; // nothing here else if (four) doFour(); else launchRocket();
The definition of 'Empty statement' in that specification.
Empty statement (
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