Add access to fields from collection in coditions

[NickSettler]

I suppose it would be great, if will be added access to the fields in the colletion when setting conditions property of the field.

Example

Meetings collection

field	type
id	integer
name	string
people	M2M connection
goods	O2M connection

People collection

field	type
id	integer
name	string
meetings	M2M connection -> Meetings collection

Goods collection

field	type
id	integer
name	string
meeting	M2O connection -> Meetings collection
people_who_used	M2M connection -> People collection

Explanation

I create a meeting in the meeting. Some people from people collection will come to this meeting. Each of them will bring some goods from goods collection. And each good will be used by any person in this meeting.

Idea

It would be greatful, if there will be an option to create a condition for the goods field in the meetings collection. The condition will allow to choose people_who_used of the goods only from people who mentioned in the people field meetings collection item.