digitalmars.D.bugs - [Issue 1517] New: .sort for structs behaves badly with ref opCmp
- d-bugmail puremagic.com (29/29) Sep 19 2007 http://d.puremagic.com/issues/show_bug.cgi?id=1517
- d-bugmail puremagic.com (6/6) Sep 19 2007 http://d.puremagic.com/issues/show_bug.cgi?id=1517
- d-bugmail puremagic.com (25/25) Mar 17 2010 http://d.puremagic.com/issues/show_bug.cgi?id=1517
http://d.puremagic.com/issues/show_bug.cgi?id=1517 Summary: .sort for structs behaves badly with ref opCmp Product: D Version: 1.021 Platform: PC OS/Version: Windows Status: NEW Severity: normal Priority: P2 Component: DMD AssignedTo: bugzilla digitalmars.com ReportedBy: wbaxter gmail.com This is incorrect code according to the spec but it doesn't really make sense to me why it doesn't work. So the spec says: """ For the .sort property to work on arrays of structs or unions, the struct or union definition must define the function: int opCmp(S) or int opCmp(S*). The type S is the type of the struct or union. This function will determine the sort ordering. """ But I just happened to use opCmp(ref S) and it seemed to work (everything compiled fine and ran without crashing, anyway). But it doesn't actually work. Sorting sorts improperly. I think making a ref opCmp in a struct should either be made to work (i see no reason why it should not work), or it should be made a compiler error to try to create one. Attached is a simple test. --
Sep 19 2007
http://d.puremagic.com/issues/show_bug.cgi?id=1517 Created an attachment (id=185) --> (http://d.puremagic.com/issues/attachment.cgi?id=185&action=view) Simple test --
Sep 19 2007
http://d.puremagic.com/issues/show_bug.cgi?id=1517 bearophile_hugs eml.cc changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |bearophile_hugs eml.cc Reduced test case, on dmd v2.041: struct S { int i; int opCmp(S other) { return this.i - other.i; } } void main() { S[S] aa; foreach (int i; [1, -1, 7]) aa[S(i)] = S(-i); // wrong order: assert(aa.keys.sort == [S(1), S(7), S(-1)]); } If this is a real bug (and it seems so) then I think it's serious bug, it's worse than a compiler crash, because the program runs unreliably. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Mar 17 2010