class Steep::TypeInference::ConstantEnv

def initialize(factory:, context:)

Any namespace is a module or class.
ConstantEnv receives an Names::Module as a context, not a Namespace, because this is a simulation of Ruby. 
def initialize(factory:, context:)
  @cache = {}
  @factory = factory
  @context = context
  @table = RBS::ConstantTable.new(builder: factory.definition_builder)
end

def lookup(name) 

def lookup(name)
  cache[name] ||= begin
    constant = table.resolve_constant_reference(
      factory.type_name_1(name),
      context: context.map {|namespace| factory.namespace_1(namespace) }
    )
    if constant
      factory.type(constant.type)
    end
  rescue => exn
    Steep.logger.error "Looking up a constant failed: name=#{name}, context=[#{context.join(", ")}], error=#{exn.inspect}"
    nil
  end
end