split_constraints

# File actionpack/lib/action_dispatch/routing/mapper.rb, line 183
          def split_constraints(path_params, constraints)
            constraints.each_pair do |key, requirement|
              if path_params.include?(key) || key == :controller
                verify_regexp_requirement(requirement) if requirement.is_a?(Regexp)
                @requirements[key] = requirement
              else
                @conditions[key] = requirement
              end
            end
          end