Global

The global command defines a public variable which is available anywhere in the program at any time. All references to a global refer to the same variable and must have a unique name, different from any other global variable, attribute, property, or object. It is a declaration and is not executable code.

    ! Global variable to store the number of chocolate cake slices.
    global  cake_slice_count

    global  table, chair
    global  car = Ford   ! car variable is Ford object
    global  batteries = 5        ! number started with
    global  current_color = "Viridian"

    ! Global variable to store the number of chocolate cake slices,
    ! with a starting value defined right at the start.

    global cake_slice_count = 10

Some reserved global variables are defined by the compiler:

Variable name	Used for
object	Direct object of a verb action
xobject	Indirect object
self	Self-referential object
words	Total number of words in word array
player	The player object
actor	Player, or a char. (for scripts)
location	Location of the player object
verbroutine	Current verb routine
endflag	If non-false, run EndGame
prompt	The character(s) used for the prompt (to let the player know when it’s time to type their next command next command to the game.)
objects	Total number of objects
system_status	After certain operations

The Hugo Library also defines several global variables, including:

Variable name	Used for
STATUSTYPE	The type of information used in the status bar 0 - no status 1 - score/turns 2 - time of day
TEXTCOLOR	The default color of the text that is printed for interpreters that support it
player_person	1=first, 2=second, 3=third
MAX_SCORE	Total possible score in game
FORMAT	Contains bitmap of format masks
DEFAULT_FONT	0=monospaced normal text
UNDO_OFF	Overrides undo when true
counter	Elapsed turns (or time, as desired)
score	Accumulated score
verbosity	For room descriptions 0 - BRIEF 1 - SUPERBRIEF 2 - VERBOSE
speaking	Set to whatever character the player is currently speaking to
old_location	The previous location
obstacle	if set to an object, that object prevents the player from leaving the room
light_source	Current object providing light (can be the location); set by FindLight
event_flag	event_flag value determines whether actions like waiting should be interrupted
need_newline	true when newline should be printed