71 lines
1.6 KiB
JavaScript
71 lines
1.6 KiB
JavaScript
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import _isArrayLike from "./_isArrayLike.js";
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import _xwrap from "./_xwrap.js";
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import bind from "../bind.js";
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function _arrayReduce(xf, acc, list) {
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var idx = 0;
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var len = list.length;
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while (idx < len) {
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acc = xf['@@transducer/step'](acc, list[idx]);
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if (acc && acc['@@transducer/reduced']) {
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acc = acc['@@transducer/value'];
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break;
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}
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idx += 1;
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}
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return xf['@@transducer/result'](acc);
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}
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function _iterableReduce(xf, acc, iter) {
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var step = iter.next();
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while (!step.done) {
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acc = xf['@@transducer/step'](acc, step.value);
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if (acc && acc['@@transducer/reduced']) {
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acc = acc['@@transducer/value'];
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break;
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}
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step = iter.next();
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}
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return xf['@@transducer/result'](acc);
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}
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function _methodReduce(xf, acc, obj, methodName) {
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return xf['@@transducer/result'](obj[methodName](bind(xf['@@transducer/step'], xf), acc));
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}
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var symIterator = typeof Symbol !== 'undefined' ? Symbol.iterator : '@@iterator';
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export default function _reduce(fn, acc, list) {
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if (typeof fn === 'function') {
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fn = _xwrap(fn);
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}
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if (_isArrayLike(list)) {
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return _arrayReduce(fn, acc, list);
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}
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if (typeof list['fantasy-land/reduce'] === 'function') {
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return _methodReduce(fn, acc, list, 'fantasy-land/reduce');
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}
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if (list[symIterator] != null) {
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return _iterableReduce(fn, acc, list[symIterator]());
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}
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if (typeof list.next === 'function') {
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return _iterableReduce(fn, acc, list);
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}
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if (typeof list.reduce === 'function') {
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return _methodReduce(fn, acc, list, 'reduce');
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}
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throw new TypeError('reduce: list must be array or iterable');
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}
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