allowed for
                                              compatibility reasons, see
                                              |shada-compatibility|.
   3 (SubString)       Array containing last |:substitute| replacement string.
                       Contains single entry: binary, replacement string used.
                       More entries are allowed for compatibility reasons, see
                       |shada-compatibility|.
   4 (HistoryEntry)    Array containing one entry from history.  Should have
                       two or three entries.  First one is history type
                       (unsigned integer), second is history line (binary),
                       third is the separator character (unsigned integer,
                       must be in interval [0, 255]).  Third item is only
                       valid for search history.  Possible history types are
                       listed in |hist-names|, here are the corresponding
                       numbers: 0 - cmd, 1 - search, 2 - expr, 3 - input,
                       4 - debug.
   5 (Register)        Map describing one register (|registers|).  If key
                       value is equal to default then it is normally not
                       present.  Keys:
                       Key  Type             Def   Description ~
                       rt   UInteger         0     Register type:
                                                   No  Description ~
                                                   0   |charwise-register|
                                                   1   |linewise-register|
                                                   2   |blockwise-register|
                       rw   UInteger         0     Register width. Only valid
                                                   for |blockwise-register|s.
                       rc   Array of binary  N/A   Register contents.  Each
                                                   entry in the array
                                                   represents its own line.
                                                   NUL characters inside the
                                                   line should be represented
                                                   as NL according to
                                                   |NL-used-for-Nul|.
                       ru   Boolean          false Unnamed register. Whether
                                                   the unnamed register had
                                                   pointed to this register.
                       n    UInteger         N/A   Register name: character
                                                   code in range [1, 255].
                                                   Example: |quote0| register
                                                   has name 48 (ASCII code for
                                                   zero character).
                       *    any              none  Other keys are allowed
                                                   for compatibility reasons,
                                                   see |shada-compatibility|.
   6 (Variable)        Array containing two items: variable name (binary) and
                       variable value (any object).  Values are converted
                       using the same code |msgpackparse()| uses when reading,
                       |msgpackdump()| when writing, so there may appear
                       |msgpack-special-dict|s.  If there are more then two
                       entries then the rest are ignored
                       (|shada-compatibility|).
   7 (GlobalMark)
   8 (Jump)
   10 (LocalMark)
   11 (Change)         Map containing some position description:
                       Entry      Position ~
                       GlobalMark Global mark position. |'A|
                       LocalMark  Local mark position. |'a|
                       Jump       One position