将扩展与rxjs中的其他运算符组合在一起

import { of } from 'rxjs';
import { map } from 'rxjs/operators';

const source = of(1, 2, 3);
const mapped = source.pipe(map(x => x * 2));
mapped.subscribe(console.log); // 输出：2, 4, 6

import { of } from 'rxjs';
import { filter } from 'rxjs/operators';

const source = of(1, 2, 3, 4, 5);
const filtered = source.pipe(filter(x => x % 2 === 0));
filtered.subscribe(console.log); // 输出：2, 4

import { of } from 'rxjs';
import { reduce } from 'rxjs/operators';

const source = of(1, 2, 3, 4, 5);
const reduced = source.pipe(reduce((acc, curr) => acc + curr, 0));
reduced.subscribe(console.log); // 输出：15

import { of, merge } from 'rxjs';

const source1 = of(1, 2, 3);
const source2 = of(4, 5, 6);
const merged = merge(source1, source2);
merged.subscribe(console.log); // 输出：1, 2, 3, 4, 5, 6