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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Mutable - Glossary | MDN | 1/3 | https://developer.mozilla.org/en-US/docs/Glossary/Mutable | reference | web, html, css, javascript, documentation | 2026-05-05T05:38:15.442131+00:00 | kb-cron |
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Mutable
A mutable value is one that can be changed without creating an entirely new value, in comparison with immutable values. In JavaScript, objects and arrays are mutable by default — their properties and elements can be changed without creating a new object or array. By contrast, primitive values are immutable — once a primitive value is created, it cannot be changed, although the variable that holds it may be reassigned another value.
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See also
- Immutable object on Wikipedia
- Related glossary terms: