1 | var _concat =
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2 | /*#__PURE__*/
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3 | require("./internal/_concat");
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4 |
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5 | var _curry1 =
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6 | /*#__PURE__*/
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7 | require("./internal/_curry1");
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8 |
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9 | var curryN =
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10 | /*#__PURE__*/
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11 | require("./curryN");
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12 | /**
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13 | * Creates a new list iteration function from an existing one by adding two new
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14 | * parameters to its callback function: the current index, and the entire list.
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15 | *
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16 | * This would turn, for instance, [`R.map`](#map) function into one that
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17 | * more closely resembles `Array.prototype.map`. Note that this will only work
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18 | * for functions in which the iteration callback function is the first
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19 | * parameter, and where the list is the last parameter. (This latter might be
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20 | * unimportant if the list parameter is not used.)
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21 | *
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22 | * @func
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23 | * @memberOf R
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24 | * @since v0.15.0
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25 | * @category Function
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26 | * @category List
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27 | * @sig ((a ... -> b) ... -> [a] -> *) -> ((a ..., Int, [a] -> b) ... -> [a] -> *)
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28 | * @param {Function} fn A list iteration function that does not pass index or list to its callback
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29 | * @return {Function} An altered list iteration function that passes (item, index, list) to its callback
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30 | * @example
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31 | *
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32 | * const mapIndexed = R.addIndex(R.map);
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33 | * mapIndexed((val, idx) => idx + '-' + val, ['f', 'o', 'o', 'b', 'a', 'r']);
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34 | * //=> ['0-f', '1-o', '2-o', '3-b', '4-a', '5-r']
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35 | */
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36 |
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37 |
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38 | var addIndex =
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39 | /*#__PURE__*/
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40 | _curry1(function addIndex(fn) {
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41 | return curryN(fn.length, function () {
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42 | var idx = 0;
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43 | var origFn = arguments[0];
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44 | var list = arguments[arguments.length - 1];
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45 | var args = Array.prototype.slice.call(arguments, 0);
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46 |
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47 | args[0] = function () {
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48 | var result = origFn.apply(this, _concat(arguments, [idx, list]));
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49 | idx += 1;
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50 | return result;
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51 | };
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52 |
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53 | return fn.apply(this, args);
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54 | });
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55 | });
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56 |
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57 | module.exports = addIndex; |
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