On Thu, Dec 4, 2014 at 11:35 PM, Max Leske <[email protected]> wrote:
> > > On 05 Dec 2014, at 08:02, Norbert Hartl <[email protected]> wrote: > > > > > > > > > >> Am 04.12.2014 um 23:31 schrieb Thierry Goubier < > [email protected]>: > >> > >> Hi all, > >> > >> I'm just wondering. > >> > >> Would it work to have a package format based on Fuel? > >> > > I doubt it would work cross platform. I don't know how fuel serializes > WideString, LargePositiveInteger, BoxedFloat64. These differ between > smalltalk platforms. The source as string solves that. Strings are written > as unicode string and numbers as certain number format etc. > > True. Cross dialect loading isn’t something we encourage to do with Fuel. > > @Thierry > You said something about partial loading: that will never be possible with > Fuel because of its pickle format. To select any partial graph you have to > first read the entire file and rebuild the graph first (ok, you don’t > strictly have to build the graph but you still need to read the entire > file). > Hi Max, you misunderstand what partial loading means in this context. I designed and implemented partial loading for the Parcel system in VW, and Fuel is essentially a clean reimplementation of parcels. The idea is that one does indeed read the entire object graph, but then only the parts of the graph that mate with the current class hierarchy are installed, and the bits that don't fit are stored for later. Why? So that a component can define extensions on classes in components that may not be present. Why? So that one can maintain a single logical component in a single package instead of decomposing it into independently loadable fragments. Lets take an example like Fuel itself. This may have specialised marshalling and unmarshalling extensions defined on may classes, some of which may be to do with the GUI. If we have partial loading we can load Fuel into a headless image. The extensions on the GUI classes will simply not be installed, *until* we load the GUI. Hence Fuel does not have to be decomposed every time we factor the system into subcomponents. Without partial loading Fuel must be decomposed into a series of fragments so that it can load that part that fits into the headless base, and we have to manage teh dependency to ensure the fragment that loads against the GUI is loaded when the GUI is loaded. Worse still, if we cut the GUI into two (e.g. development vs deployment tools) we have to visit the Fuel GUI component (and potentially many other component) and decompose it into two pieces. In practice this is extremely costly to maintain, verging on chaos. With partial loading things are simple. Perhaps I should have called it partial installation, but you get the idea. > > > > Norbert > > > >> Would that make loading faster? > >> > >> Does it already exist? > >> > >> Thanks, > >> > >> Thierry > > > > > -- best, Eliot
