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API Reference / @dasch-ng/rxjs-operators / filterNumber

Function: filterNumber()

filterNumber(): (source$) => Observable<number>

Defined in: filter-number.ts:24

Filters values to only allow numbers, with proper TypeScript type narrowing.

This operator removes all non-number values from the observable stream and narrows the type to number, ensuring type safety in TypeScript. Note that NaN is considered a number type in TypeScript and will pass through this filter.

Returns

An operator function that filters to only number values

(source$): Observable<number>

Parameters

source$

Observable<unknown>

Returns

Observable<number>

Example

typescript
import { of } from 'rxjs';
import { filterNumber } from '@dasch-ng/rxjs-operators';

of('hello', 42, 'world', 3.14, true, 123)
  .pipe(filterNumber())
  .subscribe(console.log);
// Output: 42, 3.14, 123

Released under the MIT License.