subroutine subroutinename ( ref(variable),variable )
call subroutinename ( ref(variable),variable )

function functionname ( ref(variable),variable )
functionname ( ref(variable),variable )

By default values are passed to Subroutines and Functions by value. This means that the value that you specify when calling the routine is copied into a variable that belongs to and is totally local to the routine.
The ref() declaration allows you to pass a reference to a variable or an array to the routine. When a routine changes the value of a referenced variable, the change is actually made to the original variable used in the routine call.

dim a(10)
call assignarray(ref(a),10)
print "total="+totalarray(ref(a),10)
end

subroutine assignarray(ref(array), arraylen)
   # set array elements
   for t = 0 to arraylen-1
      array[t]= t*t
    print array[t]
   next t
end subroutine

function totalarray(ref(array),arraylen)
   totalarray = 0
   for t = 0 to arraylen-1
      totalarray += array[t]
   next t
end function

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0.9.9.13