35 lines
1.1 KiB
TypeScript
35 lines
1.1 KiB
TypeScript
import { OperatorFunction } from '../types';
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/**
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* Emits the given constant value on the output Observable every time the source
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* Observable emits a value.
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*
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* <span class="informal">Like {@link map}, but it maps every source value to
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* the same output value every time.</span>
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*
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* 
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*
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* Takes a constant `value` as argument, and emits that whenever the source
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* Observable emits a value. In other words, ignores the actual source value,
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* and simply uses the emission moment to know when to emit the given `value`.
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*
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* ## Example
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* Map every click to the string 'Hi'
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* ```ts
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* import { fromEvent } from 'rxjs';
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* import { mapTo } from 'rxjs/operators';
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*
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* const clicks = fromEvent(document, 'click');
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* const greetings = clicks.pipe(mapTo('Hi'));
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* greetings.subscribe(x => console.log(x));
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* ```
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*
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* @see {@link map}
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*
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* @param {any} value The value to map each source value to.
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* @return {Observable} An Observable that emits the given `value` every time
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* the source Observable emits something.
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* @method mapTo
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* @owner Observable
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*/
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export declare function mapTo<T, R>(value: R): OperatorFunction<T, R>;
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