Is there a way to look at / edit the code of deepCopy in Object?
________________________________ From: Paolo Bonzini <[email protected]> To: [email protected] Sent: Friday, November 18, 2011 10:49 AM Subject: Re: [Help-smalltalk] Works in Squeak but not GNU (deepCopy?) On 11/18/2011 01:42 PM, Jimmy Johnson wrote: > I don't know where else to turn for help so...if one of you experts > would have the time to look at this project and see if an obvious > problem jumps out, and let me know, I would really appreciate it. > > The project is to write a rational number class and include > units/dimensions (meters/length). The system works fine in Squeak > SmallTalk, but fails in gnu SmallTalk. I'm guessing it has something > to do with my use of deepClone. Yes, that's correct. deepCopy is not standardized, but it traditionally made only a 1-level deep copy. The better way to do it in GNU Smalltalk is to use "copy" and add postCopy methods such as Unitable>>postCopy unitsImp := unitsImp collect: [ :each | each copy ] DimensionedRational>>postCopy unitsImp := unitsImp copy etc. >From a quick read of the code I'm not sure where you actually need deeper >copies, so the above is likely incomplete or incorrect. As an aside, I suggest that you replace all uses of "self length" with simply "1" (why is length special?) and merge the Constants and Dimensionable classes. Also, the Comparable class is exactly the same as Magnitude, except that it doesn't test the precondition that the classes are the same. In general such preconditions hamper the usage of polymorphism, so they're not used in Smalltalk. Paolo _______________________________________________ help-smalltalk mailing list [email protected] https://lists.gnu.org/mailman/listinfo/help-smalltalk _______________________________________________ help-smalltalk mailing list [email protected] https://lists.gnu.org/mailman/listinfo/help-smalltalk
