import _concat from "./internal/_concat.js"; import _curry1 from "./internal/_curry1.js"; import curryN from "./curryN.js"; /** * Creates a new list iteration function from an existing one by adding two new * parameters to its callback function: the current index, and the entire list. * * This would turn, for instance, [`R.map`](#map) function into one that * more closely resembles `Array.prototype.map`. Note that this will only work * for functions in which the iteration callback function is the first * parameter, and where the list is the last parameter. (This latter might be * unimportant if the list parameter is not used.) * * @func * @memberOf R * @since v0.15.0 * @category Function * @category List * @sig ((a ... -> b) ... -> [a] -> *) -> ((a ..., Int, [a] -> b) ... -> [a] -> *) * @param {Function} fn A list iteration function that does not pass index or list to its callback * @return {Function} An altered list iteration function that passes (item, index, list) to its callback * @example * * const mapIndexed = R.addIndex(R.map); * mapIndexed((val, idx) => idx + '-' + val, ['f', 'o', 'o', 'b', 'a', 'r']); * //=> ['0-f', '1-o', '2-o', '3-b', '4-a', '5-r'] */ var addIndex = /*#__PURE__*/ _curry1(function addIndex(fn) { return curryN(fn.length, function () { var idx = 0; var origFn = arguments[0]; var list = arguments[arguments.length - 1]; var args = Array.prototype.slice.call(arguments, 0); args[0] = function () { var result = origFn.apply(this, _concat(arguments, [idx, list])); idx += 1; return result; }; return fn.apply(this, args); }); }); export default addIndex;