1 | var _curry2 =
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2 | /*#__PURE__*/
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3 | require("./internal/_curry2.js");
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4 |
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5 | var map =
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6 | /*#__PURE__*/
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7 | require("./map.js");
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8 | /**
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9 | * Returns a lens for the given getter and setter functions. The getter "gets"
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10 | * the value of the focus; the setter "sets" the value of the focus. The setter
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11 | * should not mutate the data structure.
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12 | *
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13 | * @func
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14 | * @memberOf R
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15 | * @since v0.8.0
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16 | * @category Object
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17 | * @typedefn Lens s a = Functor f => (a -> f a) -> s -> f s
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18 | * @sig (s -> a) -> ((a, s) -> s) -> Lens s a
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19 | * @param {Function} getter
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20 | * @param {Function} setter
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21 | * @return {Lens}
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22 | * @see R.view, R.set, R.over, R.lensIndex, R.lensProp
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23 | * @example
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24 | *
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25 | * const xLens = R.lens(R.prop('x'), R.assoc('x'));
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26 | *
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27 | * R.view(xLens, {x: 1, y: 2}); //=> 1
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28 | * R.set(xLens, 4, {x: 1, y: 2}); //=> {x: 4, y: 2}
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29 | * R.over(xLens, R.negate, {x: 1, y: 2}); //=> {x: -1, y: 2}
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30 | */
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31 |
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32 |
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33 | var lens =
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34 | /*#__PURE__*/
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35 | _curry2(function lens(getter, setter) {
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36 | return function (toFunctorFn) {
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37 | return function (target) {
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38 | return map(function (focus) {
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39 | return setter(focus, target);
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40 | }, toFunctorFn(getter(target)));
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41 | };
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42 | };
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43 | });
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44 |
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45 | module.exports = lens; |
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