/
indexOf.ts
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/
indexOf.ts
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import baseIndexOf from "./.internal/baseIndexOf";
import toInteger from "./toInteger";
/**
* Gets the index at which the first occurrence of `value` is found in `array`
* using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
* for equality comparisons. If `fromIndex` is negative, it's used as the
* offset from the end of `array`.
*
* @since 5.5.1
* @category Array
* @param array The array to inspect.
* @param value The value to search for.
* @param fromIndex The index to search from.
* @returns Returns the index of the matched value, else `-1`.
* @example
*
* ```js
* indexOf([1, 2, 1, 2], 2)
* // => 1
*
* // Search from the `fromIndex`.
* indexOf([1, 2, 1, 2], 2, 2)
* // => 3
* ```
*/
export function indexOf<T>(array: ArrayLike<T>, value: T, fromIndex?: number): number;
export function indexOf(array: any, value: any, fromIndex?: any): number {
const length = array == null ? 0 : array.length;
if (!length) {
return -1;
}
let index = fromIndex == null ? 0 : toInteger(fromIndex);
if (index < 0) {
index = Math.max(length + index, 0);
}
return baseIndexOf(array, value, index);
}
export default indexOf;