[6a3a178] | 1 | import { ObservableInput } from '../types';
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| 2 | import { Observable } from '../Observable';
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| 3 | /**
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| 4 | * Splits the source Observable into two, one with values that satisfy a
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| 5 | * predicate, and another with values that don't satisfy the predicate.
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| 6 | *
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| 7 | * <span class="informal">It's like {@link filter}, but returns two Observables:
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| 8 | * one like the output of {@link filter}, and the other with values that did not
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| 9 | * pass the condition.</span>
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| 10 | *
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| 11 | * ![](partition.png)
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| 12 | *
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| 13 | * `partition` outputs an array with two Observables that partition the values
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| 14 | * from the source Observable through the given `predicate` function. The first
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| 15 | * Observable in that array emits source values for which the predicate argument
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| 16 | * returns true. The second Observable emits source values for which the
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| 17 | * predicate returns false. The first behaves like {@link filter} and the second
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| 18 | * behaves like {@link filter} with the predicate negated.
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| 19 | *
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| 20 | * ## Example
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| 21 | * Partition a set of numbers into odds and evens observables
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| 22 | * ```ts
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| 23 | * import { of, partition } from 'rxjs';
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| 24 | *
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| 25 | * const observableValues = of(1, 2, 3, 4, 5, 6);
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| 26 | * const [evens$, odds$] = partition(observableValues, (value, index) => value % 2 === 0);
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| 27 | *
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| 28 | * odds$.subscribe(x => console.log('odds', x));
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| 29 | * evens$.subscribe(x => console.log('evens', x));
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| 30 | *
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| 31 | * // Logs:
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| 32 | * // odds 1
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| 33 | * // odds 3
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| 34 | * // odds 5
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| 35 | * // evens 2
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| 36 | * // evens 4
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| 37 | * // evens 6
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| 38 | * ```
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| 39 | *
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| 40 | * @see {@link filter}
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| 41 | *
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| 42 | * @param {function(value: T, index: number): boolean} predicate A function that
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| 43 | * evaluates each value emitted by the source Observable. If it returns `true`,
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| 44 | * the value is emitted on the first Observable in the returned array, if
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| 45 | * `false` the value is emitted on the second Observable in the array. The
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| 46 | * `index` parameter is the number `i` for the i-th source emission that has
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| 47 | * happened since the subscription, starting from the number `0`.
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| 48 | * @param {any} [thisArg] An optional argument to determine the value of `this`
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| 49 | * in the `predicate` function.
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| 50 | * @return {[Observable<T>, Observable<T>]} An array with two Observables: one
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| 51 | * with values that passed the predicate, and another with values that did not
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| 52 | * pass the predicate.
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| 53 | */
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| 54 | export declare function partition<T>(source: ObservableInput<T>, predicate: (value: T, index: number) => boolean, thisArg?: any): [Observable<T>, Observable<T>];
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