every

The every() method checks whether all elements of an array satisfy a given condition.

Interactive example

Syntax

Classic signature

function every<
	GenericInput extends readonly unknown[]
>(
	input: GenericInput, 
	predicate: (
		element: GenericInput[number], 
		params: ArrayEveryParams<GenericInput>
	) => boolean
): boolean

Curried signature

function every<
	GenericInput extends readonly unknown[]
>(
predicate: (
	element: GenericInput[number], 
	params: ArrayEveryParams<GenericInput>
) => boolean
): (input: GenericInput) => boolean

Helper parameters

interface ArrayEveryParams<
	GenericInputArray extends readonly unknown[]
> {
	index: number;
	self: GenericInputArray;
}

Parameters

• input: The array to test.
• predicate: Predicate function that tests each element. Receives the element, its index, and the whole array.
• params.index: Position of the current element.
• params.self: The whole array (useful for comparisons or inspecting a neighbor).

Return value

true if all elements satisfy the condition, false otherwise.

See also

• some - Checks whether at least one element satisfies a condition
• find - Finds the first element that satisfies a condition

Sources

• MDN Web Docs - Array.every()