class MarketTown::Checkout::MissingDependency
When you request a dependency that is not defined in {Dependencies} then a {MissingDependency} exception will be raised. This is used to provide useful warnings in development in {Step}'s.
“` ruby container = MarketTown::Checkout::Dependencies.new
begin
container.fulfilments.propose_shipments(state)
rescue MissingDependency
puts 'Did not propose shipments'
end “`
See {AddressStep#ensure_delivery} and {DeliveryStep#validate_shipments} for real world examples.