Determine the datatype of an object within another object, even when the datatype of the object might not be

Here is the structure I am working with:

type MyType = {
  a?: {
     b: number;
  }
}

I am trying to access the type of b.

After that, my goal is to create a new type based on this:

type AnotherType = {
  mytype: MyType['a']['b']
}

However, I am facing issues with this approach.

Answer №1

To ensure null safety, you can utilize the NonNullable type:

type NewType = {
  value: NonNullable<MyValue['x']>['y']
}

Alternatively, you can make certain properties required using the Required type:

type NewType = {
  value: Required<MyValue>['x']['y']
}

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