verify_regexp_requirements

# File actionpack/lib/action_dispatch/routing/mapper.rb, line 259
          def verify_regexp_requirements(requirements, wildcard_options)
            requirements.each do |requirement, regex|
              next unless regex.is_a? Regexp

              if ANCHOR_CHARACTERS_REGEX.match?(regex.source)
                raise ArgumentError, "Regexp anchor characters are not allowed in routing requirements: #{requirement.inspect}"
              end

              if regex.multiline?
                next if wildcard_options.key?(requirement)

                raise ArgumentError, "Regexp multiline option is not allowed in routing requirements: #{regex.inspect}"
              end
            end
          end