I have encounter a few times in multiple applications an scenario in which I don't know the properties of an object but I do know that all its properties are of a certain type.

For example:

interface Metadata {
  key: string,
  value: any
}

var metadata = {
  someReducer: Metadata ,
  anotherReducer: Metadata , 
  // ...
}

In this scenario:

• I don't know the property names or number of properties of metadata
• I do know that Metadata is the type of all the properties of metadata

Now let's imagine that a function take the metadata object as argument:

function doSomething(metadata: any) {
  // ...
}

I used any as the type of the argument metadata but It would be great if I could let developers know that all the properties of this object must be of type Metadata.

is there any way to create such type annotation?