lastIndexOf.js
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var baseFindIndex = require('./_baseFindIndex'),
baseIsNaN = require('./_baseIsNaN'),
strictLastIndexOf = require('./_strictLastIndexOf'),
toInteger = require('./toInteger');
/* Built-in method references for those with the same name as other `lodash` methods. */
var nativeMax = Math.max,
nativeMin = Math.min;
/**
* This method is like `_.indexOf` except that it iterates over elements of
* `array` from right to left.
*
* @static
* @memberOf _
* @since 0.1.0
* @category Array
* @param {Array} array The array to inspect.
* @param {*} value The value to search for.
* @param {number} [fromIndex=array.length-1] The index to search from.
* @returns {number} Returns the index of the matched value, else `-1`.
* @example
*
* _.lastIndexOf([1, 2, 1, 2], 2);
* // => 3
*
* // Search from the `fromIndex`.
* _.lastIndexOf([1, 2, 1, 2], 2, 2);
* // => 1
*/
function lastIndexOf(array, value, fromIndex) {
var length = array == null ? 0 : array.length;
if (!length) {
return -1;
}
var index = length;
if (fromIndex !== undefined) {
index = toInteger(fromIndex);
index = index < 0 ? nativeMax(length + index, 0) : nativeMin(index, length - 1);
}
return value === value
? strictLastIndexOf(array, value, index)
: baseFindIndex(array, baseIsNaN, index, true);
}
module.exports = lastIndexOf;