How to dereference, remove inherited key or override it as undefined

[netmilk]

When I inherit or mix one type from some other type which contain someKey. How can I remove in the mixed or inherited object?

It's something equivalent to JS obj.key = undefined or delete obj.key

[honzajavorek]

A hack could be probably to redefine it with optional, but haven't tried it.

[maranomynet]

+1 Exclude keyword is sorely needed - or a null/undefined type.

optional doesn't really capture it, so I've used a workaround similar to this:

# Data Structures

## Comment_Bare  (object)
+ body (string)
+ author (string)

## Comment  (Comment_Bare)
+ id (string)
+ date_posted (string)

And then the POST Action uses Comment_Bare as playload, while the GET Action returns a full Comment object. It feels like a kludge.

Instead I'd like to define the POST Action playload to be Comment - but Excluding id and date_posted.