The m17n library loads a list of charset definitions from the data of tag <charset-list>. The data is loaded as a plist of this format.
CHARSET-LIST ::= DEFINITION *
DEFINITION ::= ( NAME ( KEY VALUE ) * )
NAME ::= SYMBOL
KEY ::= SYMBOL
VALUE ::= SYMBOL | INTEGER | MTEXT | PLIST
NAME is a name of a charset to define.
KEY and VALUE pair is a property given to the function mchar_define_charset() as an element of the second argument plist.