On Tue, May 17, 2005 at 12:00:59PM -0400, Paul Koning wrote: > I'm upgrading to V4.0.0 and struggling with some code that's seriously > into templates. One puzzling error is this one: > > keyed_obj.hh:159: error: no matching function for call to > 'CxnIndex::CxnIndex(CxnIndex)' > Indeces.hh:150: note: candidates are: CxnIndex::CxnIndex(CxnIndex&) > Indeces.hh:145: note: ... and some more > > It's not entirely clear to me why something very much like a copy > constructor is being invoked in the first place. But the bigger > puzzle is: why isn't the copy constructor being matched? I would have > thought that any call with a T argument should match a function or > method with an &T argument in its declaration...
CxnIndex::CxnIndex(CxnIndex&) is not a general copy constructor. Notice the non-const reference. The error message is saying that it's trying to pass a temporary to a copy constructor. You would need CxnIndex::CxnIndex(const CxnIndex&) to match that. As for why you need a copy constructor, we'd have to see the code for that, but this list isn't really the right place for helping you debug this problem further.
