18 lines
472 B
JavaScript
18 lines
472 B
JavaScript
function reduce(map, callback, initialValue) {
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if (initialValue == null && map.size === 0) {
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throw new TypeError('Reduce of empty map with no initial value');
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}
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let accumulator = initialValue;
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for (const [key, value] of map) {
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if (accumulator == null) {
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accumulator = value;
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}
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else {
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accumulator = callback(accumulator, value, key, map);
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}
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}
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return accumulator;
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}
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export { reduce };
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