When the data, manipulated by the application is stored in PCE, the normal way is to attach all this information to a single object (normally a hash_table, sheet or chain) and save this object to a file. All attached objects (i.e. all data needed by the application to save its persistent data) are then saved in the file.

PCE's save and load functionality has a limited way to deal with versions. The conversion activities are described with source_sink<-object.

Diagnostics:

• Do not know how to save <object> Object cannot be saved because it contains alien references and no defined behaviour to take care of them. This is the case with most objects that refer directly to the X-window system (e.g. windows, cursors, etc.).

  Diagnostics related to opening, writing and closing a file are applicable as well.

  Bugs:

• User-defined classes currently cannot define private save and load behaviour.

  See also

  - !cannot_save_object
  - source_sink->check_object
  - object<-clone
  - source_sink<-object
  - class-save_style
  - topic Saving to File