Null
A null is a comment or a blank line, which is
ignored by the language processor but
make an exec easier to read.
- Comments (lines 1 through 4, 8 through 11, 16)
A comment begins with /* and ends with */. Comments can be on one or more lines or on part of a line. You can put information in a comment that might not be obvious to a person reading the REXX instructions. Comments at the beginning can describe the overall purpose of the exec and perhaps list special considerations. A comment next to an individual instruction can clarify its purpose.
Note: To prevent incompatibilities with CLISTs, IBM® recommends that all REXX execs start with a comment that includes the characters "REXX" within the first line (line 1) of the exec. Failure to do so can lead to unexpected or unintended results in your REXX exec. This type of comment is called the REXX exec identifier and immediately identifies the program to readers as a REXX exec and also distinguishes it from a CLIST. It is necessary to distinguish execs from CLISTs when they are both stored in the system file, SYSPROC. For more information about where and how execs are stored, see Running an Exec Implicitly. - Blank lines (lines 6, 18)
Blank lines help separate groups of instructions and aid readability. The more readable an exec, the easier it is to understand and maintain.