58 lines
1.5 KiB
JavaScript
58 lines
1.5 KiB
JavaScript
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import _curry2 from "./internal/_curry2.js";
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import _reduce from "./internal/_reduce.js";
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/**
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* Splits a list into sub-lists, based on the result of calling a key-returning function on each element,
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* and grouping the results according to values returned.
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*
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* @func
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* @memberOf R
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* @since v0.28.0
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* @category List
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* @typedefn Idx = String | Int | Symbol
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* @sig Idx a => (b -> a) -> [b] -> [[b]]
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* @param {Function} fn Function :: a -> Idx
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* @param {Array} list The array to group
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* @return {Array}
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* An array of arrays where each sub-array contains items for which
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* the String-returning function has returned the same value.
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* @see R.groupBy, R.partition
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* @example
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* R.collectBy(R.prop('type'), [
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* {type: 'breakfast', item: '☕️'},
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* {type: 'lunch', item: '🌯'},
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* {type: 'dinner', item: '🍝'},
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* {type: 'breakfast', item: '🥐'},
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* {type: 'lunch', item: '🍕'}
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* ]);
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*
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* // [ [ {type: 'breakfast', item: '☕️'},
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* // {type: 'breakfast', item: '🥐'} ],
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* // [ {type: 'lunch', item: '🌯'},
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* // {type: 'lunch', item: '🍕'} ],
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* // [ {type: 'dinner', item: '🍝'} ] ]
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*/
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var collectBy =
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/*#__PURE__*/
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_curry2(function collectBy(fn, list) {
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var group = _reduce(function (o, x) {
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var tag = fn(x);
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if (o[tag] === undefined) {
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o[tag] = [];
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}
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o[tag].push(x);
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return o;
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}, {}, list);
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var newList = [];
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for (var tag in group) {
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newList.push(group[tag]);
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}
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return newList;
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});
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export default collectBy;
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