First, if you landed on this topic because you encountered this SAS message:
ERROR 180-322: Statement is not valid or it is used out of proper order.
...then I'll tell you right now: you've probably left off a semicolon in one of your SAS statements. If you're lucky, the SAS log will show you where it happened by highlighting the offending line with the "180" error number:
create table f as select * from sashelp.class;
Punctuation is important in any language. (Recommended reading: Eats, Shoots & Leaves: The Zero Tolerance Approach to Punctuation
.) It's especially important in a programming language like SAS, where semicolons are the only way that SAS can determine where one instruction ends and the next one begins.
So why doesn't SAS just say, "Hey buddy -- you're missing a semicolon!" ? The reason is that there are other potential causes for this message. For example, if you drop in a statement that SAS just doesn't understand -- or doesn't understand in the current context -- then the error message "Statement is not valid or it is used out of proper order" pretty much says it all.
But I was curious about the error number: 180-322. Where did that come from? To find out, I had to step into the SAS Wayback Machine.
Error numbers are historical
At SAS, the "Wayback Machine" is personified in Rick Langston, a 35+ year SAS employee who is the main steward of the SAS programming language. I asked Rick about the origin of the error number 180-322, and he immediately logged in to SAS 82.4 to check the behavior.
That's right: He ran SAS 82.4 -- as in, the version of SAS that was available in 1982. He didn't even have to climb into his DeLorean and drive 88MPH. We actually have SAS 82.4 running on a mainframe at SAS. Here's the log from Rick's syntax error test:
1 S A S L O G OS SAS 82.4 MVS/XA JOB SAS824 STEP SAS
NOTE: THE JOB SAS824 HAS BEEN RUN UNDER RELEASE 82.4 OF SAS AT SAS INSTITUTE DEV
NOTE: CPUID VERSION = 00 SERIAL = 035EA6 MODEL = 2964 .
NOTE: SAS OPTIONS SPECIFIED ARE:
1 DATA TEMP; X=1; BLAH;
180: STATEMENT IS NOT VALID OR IT IS USED OUT OF PROPER ORDER.
While Rick couldn't tell me why the number was set to 180 originally, it's clear why it's there today: legacy. Automated processes depend on error codes, and you can't go changing those error codes after a world of SAS users begin to rely on them. Maybe the "180" is a reference to "180 degrees," as in "turn around and look behind you: you forgot a semicolon!"
The second part of the error code, "322", indicates a grouping of related syntax error messages. Here is a sample of other messages that you'll encounter with the -322 suffix:
75-322 Syntax error, expecting one of the following: <expected keywords>
76-322 Syntax error, statement will be ignored.
77-322 The statement is being ignored.
181-322 Procedure name misspelled.
216-322 No simple repair for the syntax error. The statement is being ignored.
That last one is my favorite but I've never seen it in action. I wonder what sequence of statements would coax the "No simple repair" message into your SAS log? If you can make it happen, let me know in the comments. It sounds like my approach when my family asks me to fix something around the house. "No simple repair -- so IGNORE." (Not recommended, by the way.)
Where to learn more about ERROR and WARNING messages
If you're just getting started with SAS programming, it's a good idea to learn how to interpret the SAS log messages. Here are some papers that help: