Defining NaturalX Objects

General syntax of DEFINE DATA OBJECT:

DEFINE DATA  
  OBJECT

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 USING

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 local-data-area

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parameter-data-area
data-definition../graphics/dot3.gif

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END-DEFINE    

This document covers the following topics:

For an explanation of the symbols used in the syntax diagram, see Syntax Symbols.

Function

The DEFINE DATA OBJECT statement is used in a subprogram or class in conjunction with NaturalX.

Syntax Description

Syntax Element Description
USING local-data-area
LDA Name:

A local data area (LDA) contains data elements which are to be used in a single Natural module. You may reference more than one data area; in that case you have to repeat the reserved words OBJECT and USING, for example: 

DEFINE DATA
  OBJECT USING DATX_L
  OBJECT USING DATX_P

  ...
END-DEFINE ;

For further information, see also Defining Fields in a Separate Data Area in the Programming Guide.

USING parameter-data-area
PDA Name:

A data area defined with DEFINE DATA OBJECT may be a parameter data area (PDA). By using a PDA as an object data area you can avoid the extra effort of creating an object data area that has the same structure as the PDA.

data-definition
Direct Data Definition:

Data can also be defined directly using the syntax shown in Direct Data Definition.

END-DEFINE
End of DEFINE DATA Statement:

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

Direct Data Definition

Data can also be defined directly using the following syntax:

 level

group-name [(array-definition)]

variable-definition
view-definition
redefinition
handle-definition

For further information, see Defining Fields within a DEFINE DATA Statement in the Programming Guide.

Syntax Element Description
level
Level Number:

Level number is a 1- or 2-digit number in the range from 01 to 99 (the leading zero is optional) used in conjunction with field grouping. Fields assigned a level number of 02 or greater are considered to be a part of the immediately preceding group which has been assigned a lower level number.

The definition of a group enables reference to a series of fields (may also be only 1 field) by using the group name. With certain statements (CALL, CALLNAT, RESET, WRITE, etc.), you may specify the group name as a shortcut to reference the fields contained in the group.

A group may consist of other groups. When assigning the level numbers for a group, no level numbers may be skipped.

A view-definition must always be defined at Level 1.
group-name
Group Name:

The name of a group. The name must adhere to the rules for defining a Natural variable name.

See also the following sections:

array-definition
Array Dimension Definition:

With an array-definition, you define the lower and upper bounds of dimensions in an array-definition.

For further information, see Array Dimension Definition.

variable-definition
Variable Definition:

A variable-definition is used to define a single field/variable that may be single-valued (scalar) or multi-valued (array).

For further information, see Variable Definition.

view-definition
View Definition:

A view-definition is used to define a view as derived from a data definition module (DDM).

For further information, see View Definition.

redefinition
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).

For further information, see Redefinition.

handle-definition
Handle Definition:

A handle identifies a dialog element in code and is stored in handle variables.