The settings in the configuration file NATCONV.INI apply to the A format. For the U format, the ICU library is used.
This document describes how Natural supports different character sets. It covers the following topics:
The support of multiple languages with different character sets represents Natural's approach towards internationalization. It can help you when using:
upper-/lower-case translation of language-specific characters;
language-specific characters in Natural identifiers, object names and library names;
language-specific characters in an operand compared with a mask definition (see MASK Option in the Programming Guide).
All check, translation and classification tables used by Natural to support language-specific characters reside in the configuration file NATCONV.INI. By default, this file is located in Natural's etc directory.
You can modify NATCONV.INI to support local or application-specific character sets.
In a standard application, NATCONV.INI need not and should not be modified, because this could lead to serious inconsistencies, in particular if Natural objects and database data are already present.
Any modifications of NATCONV.INI should be well considered and carefully performed, otherwise problems might occur that are difficult to locate.
NATCONV.INI is subdivided in sections and subsections. The following sections are defined:
| Section | Description |
|---|---|
CHARACTERSET-DEFINITION |
This section defines the name of the internal character set.
The default is "ISO8859_1".
If you choose a different character set, subsections for this character set must be contained in the sections described below. |
CASE-TRANSLATION |
This section contains the tables required for the conversion
from upper-case to lower-case which is performed when one of the following is
specified:
|
IDENTIFIER-VALIDATION
|
This section contains the tables required for the validation of
identifiers (that is, user-defined variables in source programs), object names
and library names. It contains a subsection for each defined internal character
set.
The special characters "#" (for non-database variables), "+" (for application-independent variables), "@" (for SQL and Adabas null or length indicators) and "&" (for dynamic source generation) can be redefined in this section. In addition, the set of valid first and subsequent characters for identifiers, object names and library names can be modified. Note: |
CHARACTER-CLASSIFICATION
|
This section contains the tables required for the
classification of characters, which, for example, are used when evaluating the
MASK
option. It contains a subsection for each defined internal character
set.
|
The section CHARACTERSET-DEFINITION and each subsection
contain lines which describe how characters are to be converted and which
characters are related with which attributes. These lines are represented as
follows:
line ::= key = value
key ::= name_key | range_key
name_key ::= keyword{ CHARS }
keyword ::= INTERNAL-CHARACTERSET | NON-DB-VARI | DYNAMIC-SOURCE |
GLOBAL-VARI | FIRST-CHAR | SUBSEQUENT-CHAR |
LIB-FIRST-CHAR | LIB-SUBSEQUENT-CHAR | ALTERNATE-CARET
ISASCII | ISALPHA | ISALNUM | ISDIGIT | ISXDIGIT |
ISLOWER | ISUPPER | ISCNTRL | ISPRINT | ISPUNCT |
ISGRAPH | ISSPACE
range_key ::= hexnum | hexnum-hexnum
value ::= val {, val }
val ::= hexnum | hexnum-hexnum
hexnum ::= xhexdigithexdigit | xhexdigithexdigit
Notes:
range_key variable is
specified on the left-hand side, the number of values specified on the
right-hand side must correspond to the number of values specified in the key
range, unless only one value is specified on the right-hand side, which is then
assigned to each element of the key range.
name_key variable is
specified on the left-hand side and the corresponding list of character codes
does not fit in one line, it can be continued on the next line by specifying
"name_key =" again. You must not start the lines
with leading blanks or tabulators.
| x00-x1f = x00 | All characters between "x00" and "x1f" are converted to "x00". |
| x00-x7f = x00-x7f | All characters between "x00" and "x7f" are not converted. |
| x00-x08 = x00,x01-x07,x00 | The characters "x00" and "x08" are converted to "x00" and characters between "x01" and "x07" are not converted. |
|
ISALPHA = x41-x5a,x61-x7a,xc0-xd6,xd8 |
The attribute ISALPHA is
assigned to all characters specified in these two lines.
|
| x41 = 'A' | All characters must be specified in hexadecimal format. |
| 0x00-0x1f = 0x00 | Hexadecimal values have to be specified in either of the
following ways:
xdigitdigit |
| x00-x0f = x00,x01 | The number of specified values does not correspond to the number of elements in the key range. |