--- a/src/lib/Chat.luan	Tue Oct 29 16:47:11 2024 -0600
+++ b/src/lib/Chat.luan	Tue Oct 29 22:11:40 2024 -0600
@@ -1,6 +1,9 @@
 local Luan = require "luan:Luan.luan"
 local error = Luan.error
 local ipairs = Luan.ipairs or error()
+local Table = require "luan:Table.luan"
+local concat = Table.concat or error()
+local is_empty = Table.is_empty or error()
 local Time = require "luan:Time.luan"
 local time_now = Time.now or error()
 local Db = require "site:/lib/Db.luan"
@@ -44,6 +47,21 @@
 		end )
 	end
 
+	function chat.other_users_email(user)
+		local User = require "site:/lib/User.luan"
+		local get_user_by_id = User.get_by_id or error()
+
+		local my_id = user.id
+		local t = {}
+		for _, user_id in ipairs(chat.user_ids) do
+			if user_id ~= my_id then
+				local other_user = get_user_by_id(user_id) or error()
+				t[#t+1] = other_user.email
+			end
+		end
+		return concat( t, ", " )
+	end
+
 	return chat
 end
 
@@ -57,4 +75,9 @@
 	return chats
 end
 
+function Chat.get_by_id(id)
+	local doc = Db.get_document("id:"..id)
+	return doc and doc.type=="chat" and from_doc(doc) or nil
+end
+
 return Chat