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empty

Baseline Widely available

This feature is well established and works across many devices and browser versions. Its been available across browsers since 2015 7.

empty JavaScript .

In this article

const array1 = [1, 2, 3];

// Assign all array values to 0
for (let i = 0; i < array1.length; array1[i++] = 0 /* empty statement */);

console.log(array1);
// Expected output: Array [0, 0, 0]

js
;

empty statement JavaScript (;). JavaScript block statement .

. .

js
var arr = [1, 2, 3];

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

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

: , empty statement . . killTheUniverse() if .

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

: ({}) if...else three true four else case launchRocket() .

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

Specification
ECMAScript 2027 LanguageSpecification
# sec-empty-statement

See also

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  1. JavaScript
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    77. SyntaxError: raw bracket is not allowed in regular expression with unicode flag
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    113. TypeError: cyclic object value
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    118. TypeError: invalid Array.prototype.sort argument
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    123. TypeError: "x" has no properties
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    125. TypeError: Reduce of empty array with no initial value
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    128. TypeError: X.prototype.y called on incompatible type
    129. URIError: malformed URI sequence
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    1. JavaScript
    2. Execution model
    3. Lexical
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    7. Trailing commas
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