Compiler Listing Comments - HP DDL D40 Reference Manual

DDL Language Elements

Compiler Listing Comments

DDL puts listing comments only in its compiler listing, not in the dictionary or in host-
language source-code files. Like dictionary comments, DDL has two kinds of listing
comments:
User-defined comments
Production comments
User-Defined Listing Comments
DDL always puts user-defined listing comments in its compiler listing. You cannot
suppress these comments as you can dictionary comments.
A listing comment begins with an exclamation point and ends at another exclamation
point or at the end of the input line. You can include a listing comment on the same line
as a DDL statement. You cannot include a listing comment on the same line as a
compiler command.
A listing comment can be on a line by itself; for example:
!Suppress the listing of dictionary comments
?NOCLISTIN
You can also put listing comments between clauses in a statement; for example:
DEFINITION empnum !employee#! PIC 9(4). ! used by EMPLOYEE
An exclamation point ends the first comment, and the end of the input line ends the
second comment.
Production Comments
DDL always puts production comments in the compiler listing. Production comments
follow the name of each compiled element to describe the compilers actions.
Production comments include error and warning messages.
Like user-defined listing comments, production comments occur only in the listing. You
cannot suppress any production comments except warning messages, which you can
suppress by issuing a NOWARN command.
Data Definition Language (DDL) Reference Manual—426798-002
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Compiler Listing Comments
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