IBM Mainframe Forum

Defining Application-Independent Variables
General Syntax of DEFINE DATA INDEPENDENT:

DEFINE DATA
INDEPENDENT AIV-data-definition ...
END-DEFINE


The following topics are covered:

Function
Syntax Description
For an explanation of the symbols used in the syntax diagrams, see Syntax Symbols.


--------------------------------------------------------------------------------

Function
The DEFINE DATA INDEPENDENT statement is used to define application-independent variables (AIVs).

An application-independent variable is referenced by its name, and its content is shared by all programming objects executed within one application that refer to that name. The variable is allocated by the first executed programming object that references this variable and is deallocated by the LOGON command or a RELEASE VARIABLES statement.

The optional INIT clause is evaluated in each executed programming object that contains this clause (not only in the programming object that allocates the variable).



Syntax Description
INDEPENDENT AIV-data-definition The DEFINE DATA INDEPENDENT statement can be used to define a single or multiple application-independent variables (AIVs). For each AIV, the syntax shown below applies.

END-DEFINE The Natural reserved word END-DEFINE must be used to end the DEFINE DATA statement.


AIV Data Definition

level variable-definition
redefinition
handle-definition


Syntax Element Description:

level An application-independent variable must be defined at Level 01. Other levels are only used in a redefinition.
variable-definition A variable definition is used to define a single field/variable that may be single-valued (scalar) or multi-valued (array). See Variable Definition.

Note:
The name of an application-independent variable must start with a "+" character.

redefinition A redefinition may be used to redefine a group, a view, a DDM field or a single field/variable (that is a scalar or an array). See Redefinition.

The fields resulting from the redefinition must not be application-independent variables, that is their name must not start with a '+'. These fields are treated as local variables.

handle-definition A handle identifies a dialog element in code and is stored in handle variables. See Handle Definition.

Note:
The first character of the name must be a "+". Rules for Natural variable names apply, see Naming Conventions for User-Defined Variables (in the Natural Programming Guide).

DEFINE DATA INDEPENDENT
1 +NAME (A10) INIT <'DIPTI'>
END-DEFINE
WRITE NOTITILE '+NAME IN PROG =' +NAME
CALLNAT 'TESTAIV1'
END

DEFINE DATA LOCAL
1 #NAME (A10)
END-DEFINE
#NAME := +NAME
WRITE '#NAME IN SUB-PROG = ' #NAME
END

MORE,
+NAME IN PROG = DIPTI
#NAME IN SUB-PROG =  DIPTI