7.2.1 Emphasizing text

Text emphasis is a combination of old plaintext conventions in Usenet and E-mail and the doxygen version of markdown. Table 1 shows the font-changing constructions. The phrase limited context means that

• The opening * or _ must be preceeded by white space or a character from the set <{([,:; and must be followed by an alphanumerical character.
• The closing * or _ may not be followed by an alphanumerical character and may not be preceeded by white space or a character from the set ({[<=+-\@.
• The scope of these operations is always limited to the identified structure (paragraph, list item, etc.)

Note that =<identifier>= is limited to a an identifier, such as a file name, XML name, etc. Identifiers must start and end with an alphanumerical character, while characters from the set .-/: may appear internally. Note that this set explicitly does not allow for white space in code spans delimited by a single =. This markup is specifically meant to deal with code that is either not Prolog code or invalid Prolog code. Valid Prolog code should use the backtick as described in section 7.2.2.