Array.prototype.every() check returns true on an empty array

[marciamoss]

MDN URL

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/every

What specific section or headline is this issue about?

Array.prototype.every()

What information was incorrect, unhelpful, or incomplete?

When array is empty the check returns true for any condition

What did you expect to see?

I would expect a false if there are no elements to satisfy the condition.

Do you have any supporting links, references, or citations?

No response

Do you have anything more you want to share?

No response

MDN metadata

Page report details

• Folder: en-us/web/javascript/reference/global_objects/array/every
• MDN URL: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/every
• GitHub URL: https://github.com/mdn/content/blob/main/files/en-us/web/javascript/reference/global_objects/array/every/index.md
• Last commit: 57375b7
• Document last modified: 2023-11-27T08:17:23.000Z

[Josh-Cena]

This is already mentioned on this page.

every acts like the "for all" quantifier in mathematics. In particular, for an empty array, it returns true. (It is vacuously true that all elements of the empty set satisfy any given condition.)

if there are no elements to satisfy the condition.

"Everything satisfies X" does not require "something that satisfies X" to exist. If it helps, understand it as "nothing falsifies X".