zip() After non-eqJoin Commands

[ChrisTalman]

The RethinkDB documentation suggests that the following query is legal:

r
	.table('players')
	.eqJoin('gameId', r.table('games'))
	.without({right: 'id'})
	.zip()

However, the current type definition does not allow this, as commands like without() return an RStream, rather than an RStreamJoin.

Is there something we can do to rectify this? I've tried to look into the type definition to resolve this, but I haven't been able to find an approach so far.