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Class 'Subject<T>' incorrectly extends base class 'Observable<T>' with TypeScript 2.4

See original GitHub issue

RxJS version: 5.4.1

Code to reproduce: Save this line this to a TypeScript file (test.ts): import {Subject} from 'rxjs/Subject'; Then compile: tsc test.ts

Expected behavior: No errors

Actual behavior: Compilation error:

node_modules/rxjs/Subject.d.ts(16,22): error TS2415: Class 'Subject<T>' incorrectly extends base class 'Observable<T>'.
  Types of property 'lift' are incompatible.
    Type '<R>(operator: Operator<T, R>) => Observable<T>' is not assignable to type '<R>(operator: Operator<T, R>) => Observable<R>'.
      Type 'Observable<T>' is not assignable to type 'Observable<R>'.
        Type 'T' is not assignable to type 'R'.

Additional information: TypeScript version: 2.4.1

TypeScript 2.4 introduced stricter checks for generics (see this blog post)

(Looks like this could be a typo in Observable#lift)

Issue Analytics

State:
Created 6 years ago
Comments:14 (2 by maintainers)

Top GitHub Comments

8reactions

Argon2000commented, Aug 8, 2017

Fixed by updating RxJS to 5.4.2

3reactions

am0wacommented, Aug 14, 2017

@dearfog TypeScript to 2.4.0

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