/***@page m17nDatabaseFormat DatabaseFormat
-This section describes the formats of predefined @e plist @e type data
-in the m17n database.
+This section describes the data formats used in the m17n database.
@section dbformat General format
-The m17n library expects that the function mdatabase_load () returns a
-plist of a specific format on loading data identified by a specific
-set of tags. As the plist format used for the database data is
-strongly limited, we can use the equivalent text of simple syntax
-(S-expression) to represent the plist as below.
-
-The text consists of one or more @e elements . Each element
-represents a property, i.e. a single element of a plist, and the
-sequence of the elements constitute a plist.
-
-Elements are separated by one or more @e whitespaces, i.e. a space
+The mdatabase_load () function receives a set of tags and returns the
+contents of database in the form of plist. The keys of the returned
+plist are limited to <tt>Minteger</tt>, <tt>Msymbol</tt>,
+<tt>Mtext</tt>, and <tt>Mplist</tt>. The type of the value is
+unambiguously determined by the corresponding key. If the key is
+<tt>Minteger</tt>, the value is an integer. If the key is
+<tt>Msymbol</tt>, the value is a symbol. And so on.
+
+A number of character representations are possible to represent a
+plist. For instance, we can use the form <tt>(K1:V1, K2:V2,
+... ,Kn:Vn)</tt> to represent a plist whose first property key and
+value are K1 and V1, second key and value are K2 and V2, and so on.
+However, we can use a simpler notation here because the types of
+plists used in the m17n database are fairly restricted.
+
+Hereafter, we use a character representation, which is similar to
+S-expression, to represent a plist. (Actually, the default database
+loader of the m17n library is designed to read data files written in
+this format.)
+
+The representation consists of one or more <i>elements</i>. Each
+element represents a property, i.e. a single element of a plist.
+
+Elements are separated by one or more <i>whitespaces</i>, i.e. a space
(code 32), a tab (code 9), or a newline (code 10). Comments begin
with a semicolon (<tt>;</tt>) and extend to the end of the line.
The key and the value of each property are determined based on the
-form of element as below:
+type of the element as explained below.
<ul>
<li> INTEGER
-An element that matches the regular expression @c -?[0-9]+ or @c
-0[xX][0-9A-Fa-f]+ represents a property whose key is @c Minteger . An
-element matching the former expression is interpreted as an integer in
-decimal notation, and one matching the latter expression is
-interpreted as an integer in hexadecimal notation. The resulting
-integer is the value of the property.
+An element that matches the regular expression <tt>-?[0-9]+</tt> or
+<tt>0[xX][0-9A-Fa-f]+</tt> represents a property whose key is
+<tt>Minteger</tt>. An element matching the former expression is
+interpreted as an integer in decimal notation, and one matching the
+latter is interpreted as an integer in hexadecimal notation. The
+value of the property is the result of interpretation.
-For instance, the element 0xA0 represents a property whose value is
-the integer 160.
+For instance, the element <tt>0xA0</tt> represents a property whose value is
+160 in decimal.
<li> SYMBOL
-An element that matchs the regular expression @c
-[^-0-9(]([^\\()]|\\.)+ represents a property whose key is @c Msymbol .
-In the sequence, @c \\t , @c \\n , @c \\r , and @c \\e are replaced
-with tab (code 9), newline (code 10), carriage return (code 13), and
-escape (code 27) respectively. Other characters following a backslash
-is interpreted as it is. The symbol having the name of the resulting
-sequence is the value of the property.
+An element that matches the regular expression
+<tt>[^-0-9(]([^\\()]|\\.)+</tt> represents a property whose key is
+<tt> Msymbol</tt>. In the element, <tt>\\t</tt> , <tt>\\n</tt>,
+<tt>\\r</tt>, and <tt>\\e</tt> are replaced with tab (code 9), newline
+(code 10), carriage return (code 13), and escape (code 27)
+respectively. Other characters following a backslash is interpreted
+as it is. The value of the property is the symbol having the
+resulting string as its name.
For instance, the element <tt>abc\ def</tt> represents a property
-whose value is the symbol of name "abc def".
+whose value is the symbol having the name "abc def".
<li> M-TEXT
-An element that matches the regular expression @c "([^"]|\\")*"
-represents a property whose key is @c Mtext . The backslash escape
+An element that matches the regular expression <tt>"([^"]|\\")*"</tt>
+represents a property whose key is <tt>Mtext</tt>. The backslash escape
explained above also applies here. Moreover, each part in the
-sequence matching the regular expression @c
-\\[xX][0-9A-Fa-f][0-9A-Fa-f] is replaced with its hexadecimal
+element matching the regular expression <tt>
+\\[xX][0-9A-Fa-f][0-9A-Fa-f]</tt> is replaced with its hexadecimal
interpretation.
After having resolved the backslash escapes, the byte sequence between
<li> PLIST
-An element that is preceded by a left parenthesis, followed zero or
-more elements, and terminated by a right parenthesis represents a
-property whose key is @c Mplist . Parentheses also serve as a
-separator, which means whitespaces before and after a parenthesis can
-be omitted. The value of the property is a plist, which is the result
-of recursive interpretation of the elements between the parentheses.
+Zero or more elements surrounded by a pair of parentheses represent a
+property whose key is <tt>Mplist</tt>. Whitespaces before and after a
+parenthesis can be omitted. The value of the property is a plist,
+which is the result of recursive interpretation of the elements
+between the parentheses.
</ul>
EXAMPLE
-Suppose (K1:V1, K2:V2, ... ,Kn:Vn) represents a plist whose first
-property key and value are K1 and V1, second key and value are K2 and
-V2, and so on. Then the line:
+Here is an example of plist that is written in our S-expression like
+representation.
+
@verbatim
abc 123 (pqr 0xff) "m\"text" (_\\_ ("string" xyz) -456)
@endverbatim
-is interpreted as follows.
+
+It represents the following plist:
+
@verbatim
(Msymbol:abc,
Minteger:123,
Minteger:-456))
@endverbatim
-The default database loader of the m17n library actually read a text
-of this syntax from the database file.
-
-Here after we describes the plist format of each data by this syntax.
-
@section fontenc Font Encoding
The m17n library loads information about the encoding of each font
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