Xerox 4112-4127 Enterprise Printing System-192 - Manual (Page 181)

Using LCDS Print Description Language 3-1
3. Using logical processing
Logical, or special, processing enables you to specify logical
functions that will be performed on a record or a set of records.
During job processing, the system tests the value of a specified
test expression and directs the flow of processing based on the
result of the test.
In order to specify a logical processing function, you must define
constants (character strings or values) for which the system will
look in the job data records, and the criteria (such as “equal,”
“greater than,” and so forth) that will be used to compare the
record to the specified constant.
Types of commands for logical processing
Two types of commands are used to specify logical processing:
•
Constant definition commands. Two commands,
CRITERIA and TABLE, define the constants or conditions in
the job for which the system will test during job processing.
• Logical processing commands. These commands specify
which criteria the system will test for, and the action the
system will perform when it encounters one of these criteria.
Coding order of
command types
When you are creating a JSL that uses logical processing, you
code the component commands in the following order:
1. Code the TABLE command first to define your constants (if
any are needed). These must precede the CRITERIA
CONSTANT command that references them.
2. Code the CRITERIA commands next. These commands
must come after the tables they reference.
3. Code the logical processing commands after you have coded
the CRITERIA commands that they reference.