DragonFly On-Line Manual Pages

mdbGeneral(5)                    Version 1.5.5                   mdbGeneral(5)

NAME
       mdbGeneral - General Format

DESCRIPTION
       The mdatabase_load() function returns the data specified by tags in the
       form of plist if the first tag is not Mchartable nor Mcharset. The keys
       of the returned plist are limited to Minteger, Msymbol, Mtext, and
       Mplist. The type of the value is unambiguously determined by the
       corresponding key. If the key is Minteger, the value is an integer. If
       the key is Msymbol, the value is a symbol. And so on.

       A number of expressions are possible to represent a plist. For
       instance, we can use the form (K1:V1, K2:V2, ..., Kn:Vn) 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
       expression here because the types of plists used in the m17n database
       are fairly restricted.

       Hereafter, we use an expression, 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 expression.)

       The expression consists of one or more elements. Each element
       represents a property, i.e. a single element of a plist.

       Elements are separated by one or more whitespaces, i.e. a space (code
       32), a tab (code 9), or a newline (code 10). Comments begin with a
       semicolon (;) and extend to the end of the line.

       The key and the value of each property are determined based on the type
       of the element as explained below.

       o INTEGER
       An element that matches the regular expression -?[0-9]+ or
       0[xX][0-9A-Fa-f]+ represents a property whose key is Minteger. 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 160
       in decimal.
       o SYMBOL
       An element that matches the regular expression [^-0-9(]([^\()]|\.)+
       represents a property whose key is  Msymbol. In the element, \t, \n,
       \r, and \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 value of the
       property is the symbol having the resulting string as its name.
       For instance, the element abc\ def represents a property whose value is
       the symbol having the name 'abc def'.
       o MTEXT
       An element that matches the regular expression '([^']|\')*' represents
       a property whose key is Mtext. The backslash escape explained above
       also applies here. r, each part in the element matching the regular
       expression  \[xX][0-9A-Fa-f][0-9A-Fa-f] is replaced with its
       hexadecimal interpretation.
       After having resolved the backslash escapes, the byte sequence between
       the double quotes is interpreted as a UTF-8 sequence and decoded into
       an M-text. This M-text is the value of the property.
       o PLIST
       Zero or more elements surrounded by a pair of parentheses represent a
       property whose key is Mplist. 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.
SYNTAX NOTATION
       In an explanation of a plist format of data, a BNF-like notation is
       used. In the notation, non-terminals are represented by a string of
       uppercase letters (including '-' in the middle), terminals are
       represented by a string surrounded by '''. Special non-terminals
       INTEGER, SYMBOL, MTEXT and PLIST represents property integer, symbol,
       M-text, or plist respectively.
EXAMPLE
       Here is an example of database data that is read into a plist of this
       simple format:

       DATA-FORMAT ::=
           [ INTEGER | SYMBOL | MTEXT | FUNC ] *

       FUNC ::=
           '(' FUNC-NAME FUNC-ARG * ')'

       FUNC-NAME ::=
           SYMBOL

       FUNC-ARG ::=
           INTEGER | SYMBOL | MTEXT | '(' FUNC-ARG ')'
       For instance, a data file that contains this text matches the above
       syntax:

       abc 123 (pqr 0xff) "m
       and is read into this plist:

       1st element: key: Msymbol,  value: abc
       2nd element: key: Minteger, value: 123
       3rd element: key: Mplist,   value: a plist of these elements:
           1st element: key Msymbol,  value: pgr
           2nd element: key Minteger, value: 255
       4th element: key: Mtext,    value: m"text
       5th element: key: Mplist,   value: a plist of these elements:
           1st element: key: Msymbol, value: __
           2nd element: key: Mplist,  value: a plist of these elements:
               1st element: key: Mtext,    value: string
            2nd element: key: Msymbol,  value: xyz
            3rd element: key: Minteger, value: -456
COPYRIGHT
       Copyright (C) 2001 Information-technology Promotion Agency (IPA)
       Copyright (C) 2001-2009 National Institute of Advanced Industrial
       Science and Technology (AIST)
       Permission is granted to copy, distribute and/or modify this document
       under the terms of the GNU Free Documentation License
       <http://www.gnu.org/licenses/fdl.html>.

                                  15 Oct 2009                    mdbGeneral(5)