<< Click to Display Table of Contents >> Navigation:  Reference > Pre-processor > Syntax

All PP commands are enclosed in square brackets. To use a [ or ] as text precede them with a ` (grave), so:

[This]

is a PP substitution, whereas:

`[This`]

is a piece of text with 6 characters.

Except within single quotes (’), blanks within square brackets are ignored by the Pre-processor.

In general, each command should appear within its own set of brackets.

PP commands fall into two classes: substitution commands and others. The others are distinguished by beginning with an asterisk (*), so any PP command not beginning with an asterisk is taken by the Pre-processor as a command to evaluate the contents of the brackets, and substitute the result into the output line as text. This evaluation involves the interpretation of the basic elements of the Pre-processor command language: indices, arithmetic expressions, database references and data set references.