-namespace
-{
-const std::string XHTML_FAMILY_ATTRIBUTE("font-family");
-const std::string XHTML_SIZE_ATTRIBUTE("font-size");
-const std::string XHTML_WEIGHT_ATTRIBUTE("font-weight");
-const std::string XHTML_WIDTH_ATTRIBUTE("font-width");
-const std::string XHTML_SLANT_ATTRIBUTE("font-slant");
-
-const std::string XHTML_COLOR_ATTRIBUTE("text-color");
-const std::string XHTML_BACKGROUND_COLOR_ATTRIBUTE("background-color");
-
-//the underlined character's attributes
-const std::string XHTML_UNDERLINE_COLOR_ATTRIBUTE("u-color");
-const std::string XHTML_UNDERLINE_HEIGHT_ATTRIBUTE("u-height");
-const std::string XHTML_UNDERLINE_TYPE_ATTRIBUTE("u-type");
-const std::string XHTML_UNDERLINE_DASH_GAP_ATTRIBUTE("u-dash-gap");
-const std::string XHTML_UNDERLINE_DASH_WIDTH_ATTRIBUTE("u-dash-width");
-
-//the strikethroughed character's attributes
-const std::string XHTML_STRIKETHROUGH_COLOR_ATTRIBUTE("s-color");
-const std::string XHTML_STRIKETHROUGH_HEIGHT_ATTRIBUTE("s-height");
-
-//the character-spacing character's attributes
-const std::string XHTML_CHARACTER_SPACING_VALUE_ATTRIBUTE("char-space-value");
-
-//NOTE: the MAX_NUM_OF_ATTRIBUTES in "markup-processor.cpp" should be updated when add a new attribute for span tag.
-
-} // namespace
-