topic Re: syntax check for the if expression in SAS language in SAS Programming

syntax check for the if expression in SAS language

VictorJiang — Wed, 11 Apr 2012 03:05:59 GMT

Hi all,

I'm writing a Java client to accept an SAS expression , validate it and passed it to the backend SAS macro as the if expression in SAS language. The entered expression will be used as 'if expression' . I want to validate the syntax before pass it to the backend. Is there any approach to syntax check it ? It seems that it's not easy to syntax check it with regular expression as the if expression in SAS language may be very complicated.

If we want to check the syntax of a where clause in SAS language, SAS/FSP data modeler and SCL could be used. Is there a similar approach for the if expression?

Thanks a lot!

Re: syntax check for the if expression in SAS language

Tom — Wed, 11 Apr 2012 04:57:41 GMT

Why not use the WHERE clause syntax check?

What you want to test is the expression. In general anything allowed in a WHERE statement is allowed in an IF statement.

Re: syntax check for the if expression in SAS language

VictorJiang — Thu, 12 Apr 2012 06:33:52 GMT

Yes, it's a solution. However, it's not the best one.

For example, the 'like' operator is legal in where statement but is illegal in an IF statement.

Re: syntax check for the if expression in SAS language

SASKiwi — Thu, 12 Apr 2012 09:37:01 GMT

I am assuming you are talking about a sub-setting IF statement, not any other type?

What about taking a different approach and submit your IF statement to SAS using SYNTAXCHECK mode and/or ERRORABEND to see if it will work OK? You would need to put the IF statement in a DATA step first but you may end up with a more reliable solution as it will pick up other types of errors apart from syntax ones.

Re: syntax check for the if expression in SAS language

VictorJiang — Sun, 15 Apr 2012 05:47:07 GMT

Great idea. Yes, I want to check only the syntax of if-then statements. It's a subset of SAS language.

I will put the if-then statement inot a DATA step step first and then submit it to SAS workspace server and check the returned log. Error will be thronw in the log if there is syntax error.