Salamun alaykum
First, I must say I did search 47:15 in the forum but i couldn't find a solid explanation in terms of grammar and coherence with other ayat that contain the word "hamr". Why do you think Allah(swt) uses this word for a river of "nonintoxicating" drink (56:19) in Jannah in 47:15 ?
I'm a little bit confused about this because i knew that the word "hamr" comes from the root of "to cover, to conceal" ,so it describes any kind of fluid which makes you drunk.
(I would also like to know what brother Joseph thinks about this ayah)