No problem Alex, (collect 'tgs '+Item (db 'nm '+Tag "BLUE")) does not seem to work for me - returns NIL. For that matter, even (collect 'tgs '+Item) returns NIL. I wonder if its because 'tgs does not have +Idx in the relation
(class +Item +Entity) (rel ttl (+IdxFold +String)) (rel tgs (+List +Joint) itm (+Tag)) (rel sts (+IdxFold +String)) Also, (mapcar '((This) (: itm)) (collect 'nm '+Tag "BLUE")) worked fine - now I see the beauty of "This" better. Btw, I had to get rid of "T" in (collect 'nm '+Tag "BLUE" NIL T 'itm) to get it to work. Regards, Kashyap On Thu, Nov 21, 2019 at 11:11 PM Alexander Burger <a...@software-lab.de> wrote: > Hi Kashyap, > > sorry, I was busy! I did not find the time to install and deeply check all > your > code. > > > > 1. Query all open items that have the given tag > > >> I think I have a workaround for my question 1 :) - if I use the status > as > >> an inline relation instead of a link that is. > > I think it makes no difference. It is OK if the status is an object. > > (collect 'tgs '+Item (db 'nm '+Tag "foo")) > > or > > (mapcan > '((Tag) > (collect 'tgs '+Item Tag) ) > (collect 'nm '+Tag "foo") ) > > > > > 2. Query all items that have "ALL" the given tags - for example all > > items tagged with RED and GREEN -> this should only generate ITEM3 > > Doesn't the above 'mapcan' do that? > > > > Okay - I've got the answer to the second question as well. I am not sure > of > > the efficiency though - I essentially collect all items that have the tag > > RED and then collect all the items that have the BLUE and then do "sect" > on > > the output lists. Is this reasonable? > > > > > > (setq L1 (mapcar '( (I) (get I 'itm)) (collect 'nm '+Tag "BLUE"))) > > > > (setq L2 (mapcar '( (I) (get I 'itm)) (collect 'nm '+Tag "RED"))) > > > Yes, I would just write > > (mapcar '((This) (: itm)) (collect 'nm '+Tag "BLUE")) > > > but using the advantage of 'collect', the following should give the same > result: > > (collect 'nm '+Tag "BLUE" NIL T 'itm) > > ☺/ A!ex > > -- > UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe >
