This section describes Natural-specific rules and naming conventions.
This section describes the naming conventions that apply when saving and/or cataloging a Natural object in a Natural system file.
The name of a Natural object can be 1 to 8 characters (listed in the following table) where the first character must be one of the following:
an upper-case alphabetical character
a number sign (#)
a plus sign (+)
If the first character is a number sign (#) or a plus sign (+), the name must consist of at least one additional character.
The name of a Natural DDM can be 1 to 32 characters (listed in the following table) where the first character must be an upper-case alphabetical character.
The name of a Natural object can consist of the following characters:
| Character | ISO Character Name | Remark |
|---|---|---|
| A - Z | Latin capital letter A - Z | Upper-case alphabetical character |
| 0 - 9 | Digit zero - digit nine | Numeric character |
| - | Hyphen-minus | Hyphen |
| _ | Low line | Underscore |
| / | Solidus | Slash |
| @ | Commercial at | |
| $ | Dollar sign | |
| & | Ampersand | Only allowed in language codes
See also Defining the Language of a Natural Object in the Programming Guide. |
| # | Number sign | Hash sign |
| + | Plus sign | Only allowed as the first character |
This section describes the naming conventions that apply to a Natural library.
The name (ID) of a library can be 1 to 8 characters and must not start with "SYS". The prefix "SYS" is reserved for Natural system libraries.
A library name must start with an upper-case alphabetical character. Any other alphabetical character must also be upper case. A library name must not contain any blank characters.
A library name can consist of the following characters:
| Character | ISO Character Name | Remark |
|---|---|---|
| A - Z | Latin capital letter A - Z | Upper-case alphabetical character |
| 0 - 9 | Digit zero - digit nine | Numeric character |
| - | Hyphen-minus | Hyphen |
| _ | Low line | Underscore |
This section describes the naming conventions that apply to a user-defined variable:
For further information on user-defined variables, refer to the section User-Defined Variables in the Programming Guide.
The name of a user-defined variable can be 1 to 32 characters long.
You can use variable names of over 32 characters (for example, in complex applications where longer meaningful variable names enhance the readability of programs); however, only the first 32 characters are significant and must therefore be unique, the remaining characters will be ignored by Natural.
The name of a user-defined variable must not be a Natural reserved keyword.
Within one Natural program, you must not use the same name for a user-defined variable and a database field, because this might lead to referencing errors (see Qualifying Data Structures in the Programming Guide).
The name of a user-defined variable can consist of the following characters:
| Character | ISO Character Name | Remark |
|---|---|---|
| A - Z | Latin capital and/or small letter A - Z |
Upper-case and/or lower-case alphabetical character Lower-case not allowed as the first character |
| 0 - 9 | Digit zero - digit nine | Numeric character |
| - | Hyphen-minus | Hyphen |
| _ | Low line | Underscore |
| / | Solidus | Slash |
| @ | Commercial at | |
| $ | Dollar sign | |
| & | Ampersand | |
| # | Number sign | Hash sign |
| + | Plus sign | Only allowed as the first character |
The first character of the name must be one of the following:
| Character | ISO Character Name | Remark |
|---|---|---|
| A - Z | Latin capital letter A - Z | Upper-case alphabetical character |
| & | Ampersand | |
| # | Number sign | Hash sign |
| + | Plus sign |
If the first character is a number sign (#), a plus sign (+) or an ampersand (&), the name must consist of at least one additional character.
Variables in a global data area (GDA) with a plus sign (+) as the first character must be defined at Level 1; see also Global Data Area in the Programming Guide. Other levels are only used in a redefinition.
A plus sign (+) as the first character of a name is only allowed for application-independent variables (AIVs) and variables in a global data area (GDA).
Names of AIVs must begin with a plus sign (+); see also
Defining
Application-Independent Variables in the description of
the DEFINE DATA statement in the Statements
documentation.
An ampersand (&) as the first character of a name is used in
conjunction with dynamic source program modification (see the
RUN statement in the
Statements documentation), and as a dynamically
replaceable character when defining processing rules; see the relevant
description in the Map
Editor documentation.
With Natural for Windows, UNIX and OpenVMS, lower-case characters entered as part of a variable name are internally converted to upper case.
Caution:
If you use lower-case characters as part of the
variable name, variable names must be unique regardless of their
case.