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- 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;
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