def call(target)
        value = target.send(field_name)
        return true if @options[:allow_nil] && value.nil?
        value = (defined?(BigDecimal) && value.kind_of?(BigDecimal)) ? value.to_s('F') : value.to_s
        error_message = @options[:message]
        precision     = @options[:precision]
        scale         = @options[:scale]
        if @options[:integer_only]
          return true if value =~ /\A[+-]?\d+\z/
          error_message ||= ValidationErrors.default_error_message(:not_an_integer, field_name)
        else
          
          
          
          
          
          
          
          if precision && scale
            
            if precision > scale && scale > 0
              return true if value =~ /\A[+-]?(?:\d{1,#{precision - scale}}|\d{0,#{precision - scale}}\.\d{1,#{scale}})\z/
            elsif precision > scale && scale == 0
              return true if value =~ /\A[+-]?(?:\d{1,#{precision}}(?:\.0)?)\z/
            elsif precision == scale
              return true if value =~ /\A[+-]?(?:0(?:\.\d{1,#{scale}})?)\z/
            else
              raise ArgumentError, "Invalid precision #{precision.inspect} and scale #{scale.inspect} for #{field_name} (value: #{value.inspect} #{value.class})"
            end
          elsif precision && scale.nil?
            
            
            return true if value.gsub(/[^\d]/, '').length <= precision
            
            return true if value =~ /\A[+-]?(?:\d{1,#{precision}}(?:\.0)?)\z/
          else
            return true if value =~ /\A[+-]?(?:\d+|\d*\.\d+)\z/
          end
          error_message ||= ValidationErrors.default_error_message(:not_a_number, field_name)
        end
        add_error(target, error_message, field_name)
        
        return false
      end