<variable>

An expression consisting of a variable is a variable reference. The value of of the variable reference is the value stored in the location to which the variable is bound. It is an error to reference an unbound variable.

Example:

[1] (define variable "this is a variable")
variable
[2] variable
"this is a variable"
[3] (define unassigned #u)
unassigned
[4] unassigned

ERROR!
  message   : variable unassigned
  irritant  : unassigned
  expression: unassigned
  continue  : possible, continue with value as obtained from variable

Error (? for help) >> ^D
[5] undefined

ERROR!
  message   : variable not found
  irritant  : undefined
  expression: undefined
  continue  : possible, continue with value as obtained from variable

Error (? for help) >> ^D
[6]