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angulartypescriptkendo-uirxjsconversational-ui

Stop interval when empty array

I'm receiving a bunch of Messages from serverside and I wanna fake the typing by adding a interval to the pipe.

I'm doing this for now:

const stream = interval(1000)
  .pipe(
  map((): Message => {
    return messages.pop();
  })
);

this.feed = merge(
  stream,
  this.local
).pipe(
  scan((acc, x) => [...acc, x], [])
);

But I want it to stop the interval once my array 'messages' is empty, could someone help me please? I have been trying to implement .TakeWhile with no success.

Thanks in advance.

Solution

  • takeWhile works fine, you'd need something like this:

    const stream = interval(1000)   
  .pipe(
     takeWhile(() => messages.length > 0),
     map(() => messages.pop()),   
  );

    I made a little example on stackblitz, I hope you can work this into your application: https://stackblitz.com/edit/typescript-sq6wxb?file=index.ts