hunk.code_window: declare module '../../Observable' {
     interface Observable<T> {
       catch: CatchSignature<T>;
     }
   }
  
hunk.labels: keep keep keep add keep keep
hunk.after_edit:     _catch: CatchSignature<T>;
  
hunk.file_path: src/add/operator/catch.ts
hunk.type: add
file: 
  import { Observable } from '../../Observable';
  import { _finally, FinallySignature } from '../../operator/finally';
  
  Observable.prototype.finally = _finally;
  
  declare module '../../Observable' {
    interface Observable<T> {
      finally: FinallySignature<T>;
    }
  }