Herman Posted May 22, 2021 Posted May 22, 2021 Hello, Maybe a more special question, but here we go. Just to see if I have a good understanding wich t comes out here : local t = layout:getVehiclesOn(signal) gives a table t with the vehicles on that track contact. ( 1 item or none ) local t = layout:getVehiclesOn($("LongTrack")) gives a table t with the vehicles on that track I want to know if there is a vehicle an the contact of the signal. In previous tests I used # for the number of items in a table. if #t ~= 0 then ( there is a vehicle on the signal , a wagon or a loc ) So far so good, my problem is solved. But t is a table, the test if t ~= {} an empty table failed, why ? Some help is welcome. Kind regards, Herman
HaNNoveraNer Posted May 22, 2021 Posted May 22, 2021 Those are only references to tables. You are comparing two different references. You could check the NEXT Operator for that. But i am not sure that works. Remember there are different kinds of members in a table.
Herman Posted May 22, 2021 Author Posted May 22, 2021 Hello @HaNNoveraNer You : "Those are only references to tables". A reference to the memory ( like a pointer ) I agree with you. Thanks for your answer ! Greetings, have a nice weekend. Herman (BE)
Goetz Posted May 22, 2021 Posted May 22, 2021 vor 7 Minuten schrieb Herman: like a pointer exactly. t and {} are two different tables. You want to know, if both have the same property (i.e. the same number of entries), but with t == {} you're asking if both are the same table.
Herman Posted May 22, 2021 Author Posted May 22, 2021 Hello Götz and Thomas, With "only references to" from Thomas I understood that I was comparing two different things. Thanks to both ! Nice regards, Herman
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