.. efun:: int save_object(string name [, int format])
  string save_object([int format])

  Encode the saveable variables of the current object into a string.

  In the first form, the string is written to the file :arg:`name`. A suffix ".c" will be stripped from the name, the suffix ".o" may be added by the master object during the check in :master:`valid_read`. Result is 0 if the save file could be created, and non-zero on a non-fatal error (file could not be written, or current object is destructed).

  In the second form the string is returned directly. If the object is destructed, the result is 0.

  In both forms, the optional :arg:`format` argument determines the format of the savefile to be written:

  -1: use the driver's native format (default).
   0: original format, used by Amylaar LPMud and LDMud <= 3.2.8.
   1: LDMud >= 3.2.9: non-lambda closures, symbols, quoted arrays can be saved.
   2: LDMUd >= 3.5.0: floats are stored in a different way, which is more compact and can store the new floats losslessly.

  .. todo:: revise form above

  It is recommended to use version 2 or higher.

  .. todo:: should this format info be pulled out into a topic which all of these reference? Should it be pulled out into a tiny unit/sidebar that is included in all of the save/restore docs to which it applies?

  A variable is considered 'saveable' if it is not declared as 'nosave' or 'static'.

  Only lfuns bound to the current object can be saved.

  :history 3.2.8 changed: - now returns a success value.
    - supports direct encoding into a string.
  :history 3.2.9 changed: added restoring of non-lambda closures, symbols, and quoted arrays, using a new savefile format version 1.
  :history 3.2.10 changed: added the :arg:`format` argument.
  :history 3.5.0 changed: added the possibility to restore version 2 with its higher float precision.

  .. seealso:: :efun:`restore_object`, :efun:`save_value`