Am Dienstag, 9. Juni 2009 schrieb Ralf Hemmecke: > > > x = y == (x.dm = y.dm) and EQ(x.ob, y.ob)$Lisp > > > > > > which I think is actually not what one wants. > > > > yes, but this None-business here does not illuminate what is really > > going on. > > As far I can tell, EQ means being identical. But (now my guess) > > But if you created another string, internally the string is stored in > another memory location. >
so we need a call by value in LISP, is this possible? > Does the following session make sense to you? perfectly, but I fear I can not use it, because, usually the data is read in from a file with entries "A" all over. O.K. I could let the insert function check that on a String level and read a second "A" only for comparison, and then put the 1st "A" into the data base. > This it what happens. Only > identical elements (i.e., stored in the same memory location) are equal. > > Ralf > > (1) -> a:String := "A" > > > (1) "A" > > Type: String > (2) -> a1:Any := a > > > (2) "A" > Type: String > (3) -> a2:Any := a > > > (3) "A" > Type: String > (4) -> (a1=a2)@Boolean > > (4) true > Type: Boolean > (5) -> b:String := "A" > > (5) "A" > Type: String > (6) -> (a=b)@Boolean > > (6) true > Type: Boolean > (7) -> a3:Any := b > > (7) "A" > Type: String > (8) -> (a1=a3)@Boolean > > (8) false > Type: Boolean > > -- Mit freundlichen Grüßen Johannes Grabmeier Prof. Dr. Johannes Grabmeier Köckstr. 1, D-94469-Deggendorf Tel.-pv. +49-(0)-991-2979-584, Tel.-mob. 0171-550-3789 Tel.-d +49-(0)-991-3615-141, Sekr. -154 Fax-p: +49-(0)-1803-5518-17745 --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "FriCAS - computer algebra system" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/fricas-devel?hl=en -~----------~----~----~----~------~----~------~--~---
