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feat(concat): can infer N types
- Removes superfluous return typing - Updates deprecation messages BREAKING CHANGE: `concat` generic signature changed. Recommend not explicitly passing generics, just let inference do its job. If you must, cast with `as`.
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Lines changed: 17 additions & 31 deletions

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‎spec-dtslint/observables/concat-spec.ts‎

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@@ -29,7 +29,7 @@ it('should accept more than 6 params', () => {
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});
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it('should return Observable<unknown> for more than 6 different types of params', () => {
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const o = concat(of(1), of('a'), of(2), of(true), of(3), of([1, 2, 3]), of(4)); // $ExpectType Observable<unknown>
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const o = concat(of(1), of('a'), of(2), of(true), of(3), of([1, 2, 3]), of(4)); // $ExpectType Observable<string | number | boolean | number[]>
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});
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it('should accept scheduler after params', () => {

‎src/internal/observable/concat.ts‎

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@@ -1,34 +1,24 @@
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import { Observable } from '../Observable';
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import { ObservableInput, SchedulerLike, ObservedValueOf } from '../types';
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import { ObservableInput, SchedulerLike, ObservedValueOf, ObservedValuesFromArray } from '../types';
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import { of } from './of';
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import { concatAll } from '../operators/concatAll';
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/* tslint:disable:max-line-length */
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/** @deprecated Use {@link scheduled} and {@link concatAll} (e.g. `scheduled([o1, o2, o3], scheduler).pipe(concatAll())`) */
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/** @deprecated remove in v8. Passing a scheduler to concat is deprecated, please use {@link scheduled} and {@link concatAll} `scheduled([o1, o2], scheduler).pipe(concatAll())` */
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export function concat<O1 extends ObservableInput<any>>(v1: O1, scheduler: SchedulerLike): Observable<ObservedValueOf<O1>>;
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/** @deprecated Use {@link scheduled} and {@link concatAll} (e.g. `scheduled([o1, o2, o3], scheduler).pipe(concatAll())`) */
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/** @deprecated remove in v8. Passing a scheduler to concat is deprecated, please use {@link scheduled} and {@link concatAll} `scheduled([o1, o2], scheduler).pipe(concatAll())` */
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export function concat<O1 extends ObservableInput<any>, O2 extends ObservableInput<any>>(v1: O1, v2: O2, scheduler: SchedulerLike): Observable<ObservedValueOf<O1> | ObservedValueOf<O2>>;
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/** @deprecated Use {@link scheduled} and {@link concatAll} (e.g. `scheduled([o1, o2, o3], scheduler).pipe(concatAll())`) */
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/** @deprecated remove in v8. Passing a scheduler to concat is deprecated, please use {@link scheduled} and {@link concatAll} `scheduled([o1, o2], scheduler).pipe(concatAll())` */
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export function concat<O1 extends ObservableInput<any>, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>>(v1: O1, v2: O2, v3: O3, scheduler: SchedulerLike): Observable<ObservedValueOf<O1> | ObservedValueOf<O2> | ObservedValueOf<O3>>;
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/** @deprecated Use {@link scheduled} and {@link concatAll} (e.g. `scheduled([o1, o2, o3], scheduler).pipe(concatAll())`) */
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/** @deprecated remove in v8. Passing a scheduler to concat is deprecated, please use {@link scheduled} and {@link concatAll} `scheduled([o1, o2], scheduler).pipe(concatAll())` */
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export function concat<O1 extends ObservableInput<any>, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>, O4 extends ObservableInput<any>>(v1: O1, v2: O2, v3: O3, v4: O4, scheduler: SchedulerLike): Observable<ObservedValueOf<O1> | ObservedValueOf<O2> | ObservedValueOf<O3> | ObservedValueOf<O4>>;
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/** @deprecated Use {@link scheduled} and {@link concatAll} (e.g. `scheduled([o1, o2, o3], scheduler).pipe(concatAll())`) */
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/** @deprecated remove in v8. Passing a scheduler to concat is deprecated, please use {@link scheduled} and {@link concatAll} `scheduled([o1, o2], scheduler).pipe(concatAll())` */
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export function concat<O1 extends ObservableInput<any>, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>, O4 extends ObservableInput<any>, O5 extends ObservableInput<any>>(v1: O1, v2: O2, v3: O3, v4: O4, v5: O5, scheduler: SchedulerLike): Observable<ObservedValueOf<O1> | ObservedValueOf<O2> | ObservedValueOf<O3> | ObservedValueOf<O4> | ObservedValueOf<O5>>;
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/** @deprecated Use {@link scheduled} and {@link concatAll} (e.g. `scheduled([o1, o2, o3], scheduler).pipe(concatAll())`) */
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/** @deprecated remove in v8. Passing a scheduler to concat is deprecated, please use {@link scheduled} and {@link concatAll} `scheduled([o1, o2], scheduler).pipe(concatAll())` */
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export function concat<O1 extends ObservableInput<any>, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>, O4 extends ObservableInput<any>, O5 extends ObservableInput<any>, O6 extends ObservableInput<any>>(v1: O1, v2: O2, v3: O3, v4: O4, v5: O5, v6: O6, scheduler: SchedulerLike): Observable<ObservedValueOf<O1> | ObservedValueOf<O2> | ObservedValueOf<O3> | ObservedValueOf<O4> | ObservedValueOf<O5> | ObservedValueOf<O6>>;
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export function concat<O1 extends ObservableInput<any>>(v1: O1): Observable<ObservedValueOf<O1>>;
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export function concat<O1 extends ObservableInput<any>, O2 extends ObservableInput<any>>(v1: O1, v2: O2): Observable<ObservedValueOf<O1> | ObservedValueOf<O2>>;
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export function concat<O1 extends ObservableInput<any>, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>>(v1: O1, v2: O2, v3: O3): Observable<ObservedValueOf<O1> | ObservedValueOf<O2> | ObservedValueOf<O3>>;
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export function concat<O1 extends ObservableInput<any>, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>, O4 extends ObservableInput<any>>(v1: O1, v2: O2, v3: O3, v4: O4): Observable<ObservedValueOf<O1> | ObservedValueOf<O2> | ObservedValueOf<O3> | ObservedValueOf<O4>>;
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export function concat<O1 extends ObservableInput<any>, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>, O4 extends ObservableInput<any>, O5 extends ObservableInput<any>>(v1: O1, v2: O2, v3: O3, v4: O4, v5: O5): Observable<ObservedValueOf<O1> | ObservedValueOf<O2> | ObservedValueOf<O3> | ObservedValueOf<O4> | ObservedValueOf<O5>>;
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export function concat<O1 extends ObservableInput<any>, O2 extends ObservableInput<any>, O3 extends ObservableInput<any>, O4 extends ObservableInput<any>, O5 extends ObservableInput<any>, O6 extends ObservableInput<any>>(v1: O1, v2: O2, v3: O3, v4: O4, v5: O5, v6: O6): Observable<ObservedValueOf<O1> | ObservedValueOf<O2> | ObservedValueOf<O3> | ObservedValueOf<O4> | ObservedValueOf<O5> | ObservedValueOf<O6>>;
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export function concat<O extends ObservableInput<any>>(...observables: O[]): Observable<ObservedValueOf<O>>;
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/** @deprecated Use {@link scheduled} and {@link concatAll} (e.g. `scheduled([o1, o2, o3], scheduler).pipe(concatAll())`) */
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export function concat<O extends ObservableInput<any>>(...observables: (O | SchedulerLike)[]): Observable<ObservedValueOf<O>>;
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export function concat<R>(...observables: ObservableInput<any>[]): Observable<R>;
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/** @deprecated Use {@link scheduled} and {@link concatAll} (e.g. `scheduled([o1, o2, o3], scheduler).pipe(concatAll())`) */
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export function concat<R>(...observables: (ObservableInput<any> | SchedulerLike)[]): Observable<R>;
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export function concat<A extends ObservableInput<any>[]>(...observables: A): Observable<ObservedValuesFromArray<A>>;
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/* tslint:enable:max-line-length */
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/**
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* Creates an output Observable which sequentially emits all values from given
@@ -127,17 +117,13 @@ export function concat<R>(...observables: (ObservableInput<any> | SchedulerLike)
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* @see {@link concatMap}
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* @see {@link concatMapTo}
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*
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* @param {ObservableInput} input1 An input Observable to concatenate with others.
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* @param {ObservableInput} input2 An input Observable to concatenate with others.
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* @param input1 An input Observable to concatenate with others.
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* @param input2 An input Observable to concatenate with others.
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* More than one input Observables may be given as argument.
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* @param {SchedulerLike} [scheduler=null] An optional {@link SchedulerLike} to schedule each
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* @param scheduler An optional {@link SchedulerLike} to schedule each
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* Observable subscription on.
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* @return {Observable} All values of each passed Observable merged into a
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* single Observable, in order, in serial fashion.
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* @static true
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* @name concat
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* @owner Observable
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*/
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export function concat<O extends ObservableInput<any>, R>(...observables: Array<O | SchedulerLike>): Observable<ObservedValueOf<O> | R> {
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return concatAll<R>()(of(...observables) as Observable<ObservedValueOf<O>>);
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export function concat<O extends ObservableInput<any>>(...observables: Array<O | SchedulerLike>): Observable<ObservedValueOf<O>> {
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// The cast with `as` below is due to the SchedulerLike, once this is removed, it will no longer be a problem.
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return concatAll<ObservedValueOf<O>>()(of(...observables) as Observable<ObservedValueOf<O>>);
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}

‎src/internal/operators/concat.ts‎

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Original file line numberDiff line numberDiff line change
@@ -25,5 +25,5 @@ export function concat<T, R>(...observables: Array<ObservableInput<any> | Schedu
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* @deprecated Deprecated in favor of static {@link concat}.
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*/
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export function concat<T, R>(...observables: Array<ObservableInput<any> | SchedulerLike>): OperatorFunction<T, R> {
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return (source: Observable<T>) => source.lift.call(concatStatic(source, ...observables));
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return (source: Observable<T>) => source.lift.call(concatStatic(source, ...(observables as any[])));
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}

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