25 lines
703 B
JavaScript
25 lines
703 B
JavaScript
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import { map } from './map';
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export function pluck(...properties) {
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const length = properties.length;
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if (length === 0) {
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throw new Error('list of properties cannot be empty.');
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}
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return (source) => map(plucker(properties, length))(source);
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}
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function plucker(props, length) {
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const mapper = (x) => {
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let currentProp = x;
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for (let i = 0; i < length; i++) {
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const p = currentProp[props[i]];
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if (typeof p !== 'undefined') {
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currentProp = p;
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}
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else {
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return undefined;
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}
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}
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return currentProp;
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};
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return mapper;
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}
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//# sourceMappingURL=pluck.js.map
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