Hi Axel, We already have a procedure to save the class structure on a file, see TStreamerInfo. Do not try to write TClass yourself to a file. The dictionary for all classes written to a file is automatically written to the file when the file is closed. Rene Brun On Tue, 30 Jul 2002 axel@fnal.gov wrote: > Hi, > > writing a TClass to file works without any problems, it's just that the > read TClass is pretty much unusable. This makes kind of sense, as > TClass is more or less a static object. But there are some cases where > storing a TClass* would be helpful, e.g.: A map from TClass* to > whatever-baseclass*, where the TClass* allows to identify and access > objects deriving from whatever-baseclass. > > Now, the suggestion I have is to make TClass store only the class name, > and when reading back, to let TClass's streamer search for the TClass > already instantiated which belongs to this class name. I believe this > would be the naive expectation of what a persistent TClass* does. > > The questions I have are: > * What do you (users and rootdev) think about that? Does it interfere > with what other people do with a persistent TClass? > * Reading a member of type TClass*, is there any way ROOT can set this > pointer to the TClass object already instatiated or will we end up with > two instatiations for the same class? > > Cheers, Axel. >
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