RxJS - catch error - Replace strategy

import { Component } from '@angular/core';
import { catchError, map } from 'rxjs/operators';
import { from, of } from 'rxjs';
// import { isNumeric } from 'rxjs/internal-compatibility';

@Component({
  selector: 'fb-root',
  template: ` <H1>Hello Rxjs</H1> `,
})
export class AppComponent {
  stream$ = from([5, 10, 15, 'hello', 20]);

  constructor() {
    this.stream$.pipe(
      map(value => {
        // if (isNumeric(value)) {  // this is an alternative to the line below
        if (typeof value === 'string') {
          throw new Error("This is not a number")
        } else {
          return value;
        }
      }),
      catchError((err) => of(0)),
    ).subscribe(
      (res) => {
        console.log(res * res)
      },
      err => console.log('Error Occurred', err),
      () => console.log('Stream Completed')
    )
  }
}