1 | import { MonoTypeOperatorFunction, SchedulerLike } from '../types';
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2 | /**
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3 | *
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4 | * Errors if Observable does not emit a value in given time span.
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5 | *
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6 | * <span class="informal">Timeouts on Observable that doesn't emit values fast enough.</span>
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7 | *
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8 | * ![](timeout.png)
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9 | *
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10 | * `timeout` operator accepts as an argument either a number or a Date.
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11 | *
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12 | * If number was provided, it returns an Observable that behaves like a source
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13 | * Observable, unless there is a period of time where there is no value emitted.
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14 | * So if you provide `100` as argument and first value comes after 50ms from
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15 | * the moment of subscription, this value will be simply re-emitted by the resulting
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16 | * Observable. If however after that 100ms passes without a second value being emitted,
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17 | * stream will end with an error and source Observable will be unsubscribed.
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18 | * These checks are performed throughout whole lifecycle of Observable - from the moment
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19 | * it was subscribed to, until it completes or errors itself. Thus every value must be
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20 | * emitted within specified period since previous value.
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21 | *
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22 | * If provided argument was Date, returned Observable behaves differently. It throws
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23 | * if Observable did not complete before provided Date. This means that periods between
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24 | * emission of particular values do not matter in this case. If Observable did not complete
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25 | * before provided Date, source Observable will be unsubscribed. Other than that, resulting
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26 | * stream behaves just as source Observable.
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27 | *
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28 | * `timeout` accepts also a Scheduler as a second parameter. It is used to schedule moment (or moments)
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29 | * when returned Observable will check if source stream emitted value or completed.
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30 | *
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31 | * ## Examples
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32 | * Check if ticks are emitted within certain timespan
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33 | * ```ts
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34 | * import { interval } from 'rxjs';
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35 | * import { timeout } from 'rxjs/operators';
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36 | *
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37 | * const seconds = interval(1000);
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38 | *
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39 | * seconds.pipe(timeout(1100)) // Let's use bigger timespan to be safe,
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40 | * // since `interval` might fire a bit later then scheduled.
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41 | * .subscribe(
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42 | * value => console.log(value), // Will emit numbers just as regular `interval` would.
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43 | * err => console.log(err), // Will never be called.
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44 | * );
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45 | *
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46 | * seconds.pipe(timeout(900))
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47 | * .subscribe(
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48 | * value => console.log(value), // Will never be called.
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49 | * err => console.log(err), // Will emit error before even first value is emitted,
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50 | * // since it did not arrive within 900ms period.
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51 | * );
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52 | * ```
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53 | *
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54 | * Use Date to check if Observable completed
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55 | * ```ts
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56 | * import { interval } from 'rxjs';
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57 | * import { timeout } from 'rxjs/operators';
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58 | *
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59 | * const seconds = interval(1000);
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60 | *
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61 | * seconds.pipe(
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62 | * timeout(new Date("December 17, 2020 03:24:00")),
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63 | * )
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64 | * .subscribe(
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65 | * value => console.log(value), // Will emit values as regular `interval` would
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66 | * // until December 17, 2020 at 03:24:00.
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67 | * err => console.log(err) // On December 17, 2020 at 03:24:00 it will emit an error,
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68 | * // since Observable did not complete by then.
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69 | * );
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70 | * ```
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71 | * @see {@link timeoutWith}
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72 | *
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73 | * @param {number|Date} due Number specifying period within which Observable must emit values
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74 | * or Date specifying before when Observable should complete
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75 | * @param {SchedulerLike} [scheduler] Scheduler controlling when timeout checks occur.
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76 | * @return {Observable<T>} Observable that mirrors behaviour of source, unless timeout checks fail.
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77 | * @method timeout
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78 | * @owner Observable
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79 | */
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80 | export declare function timeout<T>(due: number | Date, scheduler?: SchedulerLike): MonoTypeOperatorFunction<T>;
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