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Overriding Interface Properties

You can override properties from the base interface, but the new type must be compatible with the original:

interface Character {
  rank: string | number;
  name: string;
  level: number;
}

interface Wizard extends Character {
  // Wizards only have a number rank
  // This is allowed because
  // `number` is assignable to `string | number`
  rank: number;
  mana: number;
}

But you can't change to an incompatible type:

interface Character {
  rank: string;
  name: string;
  level: number;
}

interface Wizard extends Character {
  // This breaks because `number` is
  // not assignable to `string`
  rank: number;
  mana: number;
}

Assignment

The company uses a shared SystemEvent interface to represent internal system events. We need more specific system event interfaces for handling errors and outages as well as a way to filter for the high-priority events.

Create and export an interface called ErrorEvent that extends SystemEvent and overrides the following properties:
- type: "error"
- payload: string
- add a new property: code with a number type
Create and export an interface called OutageEvent that extends SystemEvent and overrides the following properties:
- type: "outage"
- severity: "critical" (all outages are considered critical)
- add a new property: durationSeconds with a number type
Complete the function getHighPriorityEvents function.
- Fix its signature, it expects an array of SystemEvent objects.
- Fix its implementation, it should return a new array of SystemEvent objects, filtering for events with a severity of "high" or "critical" (maintain order).