github-pages-deploy-action/node_modules/rxjs/_esm2015/internal/operators/pluck.js

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2020-03-07 11:45:40 +08:00
import { map } from './map';
export function pluck(...properties) {
const length = properties.length;
if (length === 0) {
throw new Error('list of properties cannot be empty.');
}
return (source) => map(plucker(properties, length))(source);
}
function plucker(props, length) {
const mapper = (x) => {
let currentProp = x;
for (let i = 0; i < length; i++) {
const p = currentProp[props[i]];
if (typeof p !== 'undefined') {
currentProp = p;
}
else {
return undefined;
}
}
return currentProp;
};
return mapper;
}
//# sourceMappingURL=pluck.js.map