POKESHIFT variable-name = axmud-object-property
POKESHIFT ARRAY variable-name = axmud-object-property

   Synopsis:
      Removes a value from the beginning of an Axmud internal list property

   Notes:
      PEEK gives Axbasic scripts access to most of Axmud's internal data (see
         the help for the PEEK statement for a full explanation).
      POKESHIFT can only be used with list properties such as
         "world.current.doorPatternList". It cannot be used with a scalar
         property such as "world.current.name", a hash property such as
         "world.current.currencyHash" or a Perl object such as "world.current".
      'variable-name' is set to the first value of the list property. In
         addition, that value is removed from the list property. If the list
         property is empty, a string variable is set to  "<<undef>>" and a
         numeric variable is set to 0.
      Much of Axmud's internal data is read-only, and cannot be modified with
         this statement. If you try to modify a read-only property you will get
         an 'operation failure' error.

   Warning:
      Do not try to modify Axmud's internal data unless you know what you are
         doing. Read the Axmud manual before you try to POKESHIFT anything. (The
         examples below are safe, but backup your data first.)

   Compatibility:
      Before Axbasic v1.002, POKESHIFT was PEEKSHIFT.

   Examples:
      ! Remove the first value from a list property and store it in an Axbasic
      ! global scalar variable
      POKESHIFT pattern$ = "world.current.doorPatternList"

      ! Remove the first value from a list property and store it in an Axbasic
      ! global array
      POKESHIFT ARRAY patterns$ = "world.current.doorPatternList"

      ! Remove the first value from a list property and store it in an Axbasic
      ! local scalar variable
      LOCAL pattern$
      POKESHIFT pattern$ = "world.current.doorPatternList"
