pluck.js
902 Bytes
/** PURE_IMPORTS_START _map PURE_IMPORTS_END */
import { map } from './map';
export function pluck() {
var properties = [];
for (var _i = 0; _i < arguments.length; _i++) {
properties[_i] = arguments[_i];
}
var length = properties.length;
if (length === 0) {
throw new Error('list of properties cannot be empty.');
}
return function (source) { return map(plucker(properties, length))(source); };
}
function plucker(props, length) {
var mapper = function (x) {
var currentProp = x;
for (var i = 0; i < length; i++) {
var p = currentProp != null ? currentProp[props[i]] : undefined;
if (p !== void 0) {
currentProp = p;
}
else {
return undefined;
}
}
return currentProp;
};
return mapper;
}
//# sourceMappingURL=pluck.js.map