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x/ramda/map.js

:ram: Practical functional Javascript
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import _curry2 from './internal/_curry2';import _dispatchable from './internal/_dispatchable';import _map from './internal/_map';import _reduce from './internal/_reduce';import _xmap from './internal/_xmap';import curryN from './curryN';import keys from './keys';

/** * Takes a function and * a [functor](https://github.com/fantasyland/fantasy-land#functor), * applies the function to each of the functor's values, and returns * a functor of the same shape. * * Ramda provides suitable `map` implementations for `Array` and `Object`, * so this function may be applied to `[1, 2, 3]` or `{x: 1, y: 2, z: 3}`. * * Dispatches to the `map` method of the second argument, if present. * * Acts as a transducer if a transformer is given in list position. * * Also treats functions as functors and will compose them together. * * @func * @memberOf R * @since v0.1.0 * @category List * @sig Functor f => (a -> b) -> f a -> f b * @param {Function} fn The function to be called on every element of the input `list`. * @param {Array} list The list to be iterated over. * @return {Array} The new list. * @see R.transduce, R.addIndex * @example * * const double = x => x * 2; * * R.map(double, [1, 2, 3]); //=> [2, 4, 6] * * R.map(double, {x: 1, y: 2, z: 3}); //=> {x: 2, y: 4, z: 6} * @symb R.map(f, [a, b]) = [f(a), f(b)] * @symb R.map(f, { x: a, y: b }) = { x: f(a), y: f(b) } * @symb R.map(f, functor_o) = functor_o.map(f) */var map = _curry2(_dispatchable(['fantasy-land/map', 'map'], _xmap, function map(fn, functor) { switch (Object.prototype.toString.call(functor)) { case '[object Function]': return curryN(functor.length, function() { return fn.call(this, functor.apply(this, arguments)); }); case '[object Object]': return _reduce(function(acc, key) { acc[key] = fn(functor[key]); return acc; }, {}, keys(functor)); default: return _map(fn, functor); }}));export default map;