# File formvalidator.rb, line 506
    def do_constraint(key, constraints)
      constraints.each do |constraint|
        type = constraint.class.to_s.intern
        case type
          when :String
            apply_string_constraint(key, constraint)
          when :Hash
            apply_hash_constraint(key, constraint)
          when :Proc
            apply_proc_constraint(key, constraint)
          when :Regexp
            apply_regexp_constraint(key, constraint) 
        end
      end
    end