Götz Becker Posted June 14, 2008 Report Share Posted June 14, 2008 Hi all, I am having another hard time understanding the reason behind things. Coming from 42 as major answer my brain won´t come to an easy answer why this works: Anyone around who would enlighten me, why this works and why it won´t work for other things inside the cluster like e.g. I32? VI is in 8.5.1 Download File:post-1037-1213351859.vi Greetings Götz Quote Link to comment
Yair Posted June 14, 2008 Report Share Posted June 14, 2008 I don't think there is any need to call Douglas Adams for this. I'm not sure if there is any reason why this works with references (it seems to work with any kind of reference), but I would expect it not to work. In any case, I'm guessing that it just type casts the reference and then compares it. That would explain why an empty reference is equal to an empty string. QUOTE (Yen @ Jun 13 2008, 03:13 PM) I'm guessing that it just type casts the reference and then compares it. Actually, attempting to compare to an existing reference crashes LabVIEW, so I'm guessing this is a bug. Quote Link to comment
Francois Normandin Posted June 14, 2008 Report Share Posted June 14, 2008 Well, "equals to" must have a polymorphic behavior to account for this because refnums cannot be concanated to strings... Therefore, it is especially built-in this function. As Yen says, it could be a bug or a development feature that was forgotten and not cleaned-up. Quote Link to comment
Götz Becker Posted June 14, 2008 Author Report Share Posted June 14, 2008 Crashing LabVIEW by feeding the equal primitive with a valid Refnum, was the first thing a coworker did, after I showed him this (yeah... on my computer... of course). Another interesting fact is the absence of a coercion dot. I guess that would point towards a deeply hidden form of typecast. Quote Link to comment
LAVA 1.0 Content Posted June 14, 2008 Report Share Posted June 14, 2008 I reported this to NI under SR# 1181201. Stand-by for a CAR#. Ben Quote Link to comment
Francois Normandin Posted June 14, 2008 Report Share Posted June 14, 2008 I could not crash LabVIEW 8.5 with the active reference equality... Quote Link to comment
LAVA 1.0 Content Posted June 14, 2008 Report Share Posted June 14, 2008 No CAR available. A future version of LV will give broken wires for this code construct. Ben Quote Link to comment
Yair Posted June 15, 2008 Report Share Posted June 15, 2008 QUOTE (normandinf @ Jun 13 2008, 06:51 PM) I could not crash LabVIEW 8.5 with the active reference equality... It does happen with the current beta - all you need to do is get a reference to the current VI (e.g. by using a VI class property node). Quote Link to comment
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