STACK

If you specify TOP, the data/program/command will be placed at the top of the Natural stack. Otherwise, they are placed at the bottom of the stack.

Example: The following statement causes the content of the variable #FIELDA to be placed as data on top of the stack:

STACK TOP #FIELDA

This option, which is also the default, causes data to be placed in the stack which are to be used as input data for an INPUT statement.

Delimiter characters or input assign characters contained within the data values will be processed as delimiters. For details on how data from the stack are processed by an INPUT statement, refer to Processing Data from the Natural Stack (in the description of the INPUT statement).

Example: The following statements cause the contents of the variables #FIELD1 and #FIELD2 to be placed in the stack:

MOVE 'ABC' TO #FIELD1
MOVE 'XYZ' TO #FIELD2
STACK #FIELD1 #FIELD2

These variables will be passed as data to the next INPUT statement in the Natural program, using delimiter mode:

INPUT #FIELD1  #FIELD2

Note:
If operand2 is a time variable (Format T), only the time component of the variable content is placed in the stack, but not the date component.

This option causes all data to be passed on a field-by-field basis to the next INPUT statement; no key assignments or delimiter characters will be interpreted.

Examples:

The following statements cause ABC,DEF to be placed in #FIELD1 and XYZ in #FIELD2:

MOVE 'ABC,DEF' TO #FIELD1
MOVE 'XYZ'     TO #FIELD2
STACK TOP DATA FORMATTED #FIELD1 #FIELD2
...
INPUT #FIELD1 #FIELD2

Assuming the input delimiter character to be the comma (profile/session parameter ID=,), the following statements - without the keyword FORMATTED - cause ABC to be placed in #FIELD1 and DEF in #FIELD2:

MOVE 'ABC,DEF' TO #FIELD1
STACK TOP DATA #FIELD1
...
INPUT #FIELD1 #FIELD2

Note:
The FORMATTED option should be used if the data to be passed contains delimiter, control or DBCS characters to avoid unintentional interpretation of these characters.

To place a command (or program name) in the stack, you specify the keyword COMMAND followed by the command specified in operand1. Natural will execute the command instead of displaying the NEXT prompt and prompting the user for input.

Example:

The following statement causes the command RUN to be placed at the top of the stack. Natural will execute this command at the point where the NEXT prompt would normally be issued.

STACK TOP COMMAND 'RUN'

Together with a command (operand1), you may also place data (operand2) in the stack. These data will then be processed by the next INPUT statement after the command has been executed.

Data stacked with a command are always stacked unformatted.

Note:
If the data to be stacked include empty alphanumeric fields (that is, blanks), these blanks will be interpreted as delimiters between values and thus not processed correctly by the corresponding INPUT statement. Therefore, if you wish to stack empty alphanumeric fields as data with a command, you have to use two STACK statements: one STACK DATA operand2 ... to stack the data, and one STACK COMMAND operand1 to stack the command.

If operand2 is a date variable, you can specify the session parameter DF as a parameter for this variable.