angular - 类型 'MonoTypeOperatorFunction' 不可分配给类型为“OperatorFunction”的参数

Question

我正在尝试进行剑道聊天示例:https://www.telerik.com/kendo-angular-ui/components/conversationalui/
我使用 Visual Studio 代码和 angular 6，我在谷歌搜索但找不到解决方案
但我收到了这个错误:

ERROR in src/app/app.component.ts(68,7): error TS2345: Argument of type 'MonoTypeOperatorFunction' is not assignable to parameter of type 'OperatorFunction'. Types of parameters 'source' and 'source' are incompatible. Type 'Observable' is not assignable to type 'Observable'. Type 'Message' is not assignable to type 'any[]'. Property 'length' is missing in type 'Message'.

我的组件是:

import { Component } from '@angular/core';    
import { Subject } from 'rxjs/Subject';
import { switchMap } from 'rxjs/operators/switchMap';
import { map } from 'rxjs/operators/map';
import { windowCount } from 'rxjs/operators/windowCount';
import { scan } from 'rxjs/operators/scan';
import { take } from 'rxjs/operators/take';
import { tap } from 'rxjs/operators/tap';
import { from } from 'rxjs/observable/from';
import { merge } from 'rxjs/observable/merge';

import { ChatModule, Message, User, Action, ExecuteActionEvent, SendMessageEvent } from '@progress/kendo-angular-conversational-ui';
import { Observable } from 'rxjs/Observable';
import { ChatService } from './chat.service';

@Component({
  providers: [ ChatService ],
  selector: 'my-app',
  template: `
      <kendo-chat
        [messages]="feed | async"
        [user]="user"
        (sendMessage)="sendMessage($event)"
      >
      </kendo-chat>
    `
})
export class AppComponent {
  public feed: Observable<Message[]>;

  public readonly user: User = {
    id: 1
  };

  public readonly bot: User = {
    id: 0
  };

  private local: Subject<Message> = new Subject<Message>();

  constructor(private svc: ChatService) {
    const hello: Message = {
      author: this.bot,
      suggestedActions: [{
        type: 'reply',
        value: 'Neat!'
      }, {
        type: 'reply',
        value: 'Thanks, but this is boring.'
      }],
      timestamp: new Date(),
      text: 'Hello, this is a demo bot. I don\t do much, but I can count symbols!'
    };

    // Merge local and remote messages into a single stream
    this.feed = merge(
      from([ hello ]),
      this.local,
      this.svc.responses.pipe(
        map((response): Message => ({
          author: this.bot,
          text: response
        })
      ))
    ).pipe(
      // ... and emit an array of all messages
      scan((acc, x) => [...acc, x], [])
    );
  }

  public sendMessage(e: SendMessageEvent): void {
    this.local.next(e.message);

    this.local.next({
      author: this.bot,
      typing: true
    });

    this.svc.submit(e.message.text);
  }
}

我收到错误的行代码是:

scan((acc, x) => [...acc, x], [])

Answer 1

我也遇到了具体问题。尝试以下修复:

scan((acc:any, x) => acc.concat(x), [])

另见: https://github.com/ReactiveX/rxjs/pull/2897#issuecomment-334654459