Angular Error: Property 'map' is not found in type 'OperatorFunction'

Question

Angular Error: Property 'map' is not found in type 'OperatorFunction'

Code:

Using map and switchMap from 'rxjs/operators'.

 import { map, switchMap } from 'rxjs/operators';

Here is the canActivate code for route guard:

  canActivate(): Observable<boolean> {
    return this.auth.userObservable
      .pipe(switchMap((user: firebase.User) => this.userService.fetch(user.uid))
      .map((user) => user.isSeller));
  }

An error is encountered with message: Property 'map' does not exist on type 'OperatorFunction'. Screenshots provided below.

https://i.sstatic.net/o0siw.png

https://i.sstatic.net/uQVnZ.png

Attempt made: Attempting to wrap map within pipe but still facing issues.

canActivate(): Observable<boolean> {
    return this.auth.userObservable
      .pipe(switchMap((user: firebase.User) => this.userService.fetch(user.uid))
      .pipe(map((user) => user.isSeller)));
  }

The above syntax is throwing errors as well. Any insights on what may be causing this issue would be greatly appreciated. Thanks in advance!

angular typescript rxjs

Answer 1

Answer №1

The code snippet containing the map operator from RxJS must be enclosed within the pipe() method.

canActivate(): Observable<boolean> {
    return this.auth.userObservable
      .pipe(
        switchMap((user: firebase.User) => this.userService.fetch(user.uid)),
        map((user) => user.isSeller)
     )
  }

Answer 2

The code snippet containing the map operator from RxJS must be enclosed within the pipe() method.

canActivate(): Observable<boolean> {
    return this.auth.userObservable
      .pipe(
        switchMap((user: firebase.User) => this.userService.fetch(user.uid)),
        map((user) => user.isSeller)
     )
  }

Answer 3

Answer №2

Remember to include all operators inside the pipe separated by commas.

 canActivate(): Observable<boolean> {
    return this.auth.userObservable
      .pipe(switchMap((user: firebase.User) => this.userService.fetch(user.uid))
      , map((user) => user.isSeller));
  }

Answer 4

Remember to include all operators inside the pipe separated by commas.

 canActivate(): Observable<boolean> {
    return this.auth.userObservable
      .pipe(switchMap((user: firebase.User) => this.userService.fetch(user.uid))
      , map((user) => user.isSeller));
  }

Answer 5

Answer №3

The reason for the error message is due to calling map on the output of switchMap (which does not have a method named map), while mistakenly closing the parenthesis.

When using pipeable operators, it is common practice to chain them as arguments in the pipe function:

obs$.pipe(op1(...), op2(...), ..., opN(...));

To fix your code, you should rewrite it as follows:

canActivate(): Observable<boolean> {
    return this.auth.userObservable
      .pipe(
         switchMap((user: firebase.User) => this.userService.fetch(user.uid)),
         map(user => user.isSeller)
      );
}

Answer 6

The reason for the error message is due to calling map on the output of switchMap (which does not have a method named map), while mistakenly closing the parenthesis.

When using pipeable operators, it is common practice to chain them as arguments in the pipe function:

obs$.pipe(op1(...), op2(...), ..., opN(...));

To fix your code, you should rewrite it as follows:

canActivate(): Observable<boolean> {
    return this.auth.userObservable
      .pipe(
         switchMap((user: firebase.User) => this.userService.fetch(user.uid)),
         map(user => user.isSeller)
      );
}

Angular Error: Property 'map' is not found in type 'OperatorFunction'

Answer №1

Answer №2

Answer №3

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