# File lib/clamp/attribute/instance.rb, line 63 def default_from_environment return if self.defined? return if attribute.environment_variable.nil? return unless ENV.has_key?(attribute.environment_variable) # Set the parameter value if it's environment variable is present value = ENV[attribute.environment_variable] begin take(value) rescue ArgumentError => e command.send(:signal_usage_error, "$#{attribute.environment_variable}: #{e.message}") end end