Inheritance of ==?

gistfile1.nim

type
  Vehicle* = ref object of RootRef
    color*: string

type
  Car* = ref object of Vehicle
    make*: string

# This method ... is never called, it seems
# that system.`==` is preferred, why?
method `==`*(self, other: Vehicle): bool =
  echo "why can't we get here?"
  true

# If we enable this method it will be used
#method `==`*(self, other: Car): bool =
#  echo "this one works"
#  true


var volvo = Car(color: "blue", make: "Volvo")
var saab = Car(color: "red", make: "Saab")

echo(volvo == saab)