42 lines
1.1 KiB
JavaScript
42 lines
1.1 KiB
JavaScript
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import _curry2 from "./internal/_curry2.js"; // `Const` is a functor that effectively ignores the function given to `map`.
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var Const = function (x) {
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return {
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value: x,
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'fantasy-land/map': function () {
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return this;
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}
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};
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};
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/**
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* Returns a "view" of the given data structure, determined by the given lens.
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* The lens's focus determines which portion of the data structure is visible.
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*
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* @func
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* @memberOf R
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* @since v0.16.0
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* @category Object
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* @typedefn Lens s a = Functor f => (a -> f a) -> s -> f s
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* @sig Lens s a -> s -> a
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* @param {Lens} lens
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* @param {*} x
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* @return {*}
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* @see R.set, R.over, R.lens, R.lensIndex, R.lensProp, R.lensPath
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* @example
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*
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* const xLens = R.lensProp('x');
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*
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* R.view(xLens, {x: 1, y: 2}); //=> 1
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* R.view(xLens, {x: 4, y: 2}); //=> 4
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*/
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var view =
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/*#__PURE__*/
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_curry2(function view(lens, x) {
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// Using `Const` effectively ignores the setter function of the `lens`,
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// leaving the value returned by the getter function unmodified.
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return lens(Const)(x).value;
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});
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export default view;
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