@reactivex/ix-es2015-cjs
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The Interactive Extensions for JavaScript
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JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.distinctUntilChanged = exports.DistinctUntilChangedAsyncIterable = void 0;
const tslib_1 = require("tslib");
const asynciterablex_js_1 = require("../asynciterablex.js");
const identity_js_1 = require("../../util/identity.js");
const comparer_js_1 = require("../../util/comparer.js");
const withabort_js_1 = require("./withabort.js");
const aborterror_js_1 = require("../../aborterror.js");
/** @ignore */
class DistinctUntilChangedAsyncIterable extends asynciterablex_js_1.AsyncIterableX {
constructor(source, keySelector, comparer) {
super();
this._source = source;
this._keySelector = keySelector;
this._comparer = comparer;
}
[Symbol.asyncIterator](signal) {
return tslib_1.__asyncGenerator(this, arguments, function* _a() {
var _b, e_1, _c, _d;
(0, aborterror_js_1.throwIfAborted)(signal);
let currentKey;
let hasCurrentKey = false;
try {
for (var _e = true, _f = tslib_1.__asyncValues((0, withabort_js_1.wrapWithAbort)(this._source, signal)), _g; _g = yield tslib_1.__await(_f.next()), _b = _g.done, !_b; _e = true) {
_d = _g.value;
_e = false;
const item = _d;
const key = yield tslib_1.__await(this._keySelector(item, signal));
let comparerEquals = false;
if (hasCurrentKey) {
comparerEquals = yield tslib_1.__await(this._comparer(currentKey, key));
}
if (!hasCurrentKey || !comparerEquals) {
hasCurrentKey = true;
currentKey = key;
yield yield tslib_1.__await(item);
}
}
}
catch (e_1_1) { e_1 = { error: e_1_1 }; }
finally {
try {
if (!_e && !_b && (_c = _f.return)) yield tslib_1.__await(_c.call(_f));
}
finally { if (e_1) throw e_1.error; }
}
});
}
}
exports.DistinctUntilChangedAsyncIterable = DistinctUntilChangedAsyncIterable;
/**
* Returns an async-iterable sequence that contains only distinct contiguous elements according to the optional keySelector and comparer.
*
* @template TSource The type of the elements in the source sequence.
* @template TKey The type of the discriminator key computed for each element in the source sequence.
* @param {DistinctOptions<TSource, TKey = TSource>} [options] The optional options for adding a key selector and comparer.
* @returns {MonoTypeOperatorAsyncFunction<TSource>} An operator that returns an async-iterable that contains only distinct contiguous items.
*/
function distinctUntilChanged(options) {
return function distinctUntilChangedOperatorFunction(source) {
const { ['keySelector']: keySelector = identity_js_1.identityAsync, ['comparer']: comparer = comparer_js_1.comparerAsync } = options || {};
return new DistinctUntilChangedAsyncIterable(source, keySelector, comparer);
};
}
exports.distinctUntilChanged = distinctUntilChanged;
//# sourceMappingURL=distinctuntilchanged.js.map