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x/ramda/lensPath.js

:ram: Practical functional Javascript
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import _curry1 from './internal/_curry1';import assocPath from './assocPath';import lens from './lens';import path from './path';

/** * Returns a lens whose focus is the specified path. * * @func * @memberOf R * @since v0.19.0 * @category Object * @typedefn Idx = String | Int * @typedefn Lens s a = Functor f => (a -> f a) -> s -> f s * @sig [Idx] -> Lens s a * @param {Array} path The path to use. * @return {Lens} * @see R.view, R.set, R.over * @example * * const xHeadYLens = R.lensPath(['x', 0, 'y']); * * R.view(xHeadYLens, {x: [{y: 2, z: 3}, {y: 4, z: 5}]}); * //=> 2 * R.set(xHeadYLens, 1, {x: [{y: 2, z: 3}, {y: 4, z: 5}]}); * //=> {x: [{y: 1, z: 3}, {y: 4, z: 5}]} * R.over(xHeadYLens, R.negate, {x: [{y: 2, z: 3}, {y: 4, z: 5}]}); * //=> {x: [{y: -2, z: 3}, {y: 4, z: 5}]} */var lensPath = _curry1(function lensPath(p) { return lens(path(p), assocPath(p));});export default lensPath;