The TRACEVARIABLES option is a DS2_OPTIONS statement option that enables you to trace changes to variable values during the execution of a DS2 program. The variable trace information is reported to the App.TableServices.DS2.Runtime.TraceVariables logger.

The TRACEVARIABLES option enables, but does not activate, the tracing of modified variable values. Variable value tracing is activated only when both of the following occur:

• The TRACEVARIABLES option is set.
• The logger level for the App.TableServices.DS2.Runtime.TraceVariables logger is set to TRACE.

If either the TRACEVARIABLES option is not set or the logger level for the App.TableServices.DS2.Runtime.TraceVariables logger is not set to TRACE, no variable tracing information is reported.

Tracing information is reported only for variables that are modified by the following types of DS2 statements:

• Assignment statement ( = )
• Array assignment statement ( := )
• Index variable assignment by a DO statement
• SET or MERGE statement
• SUBSTR ( left of = ) statement
• Sum statement ( variable + expression; variable - expression; )

Tracing information is not reported for the following:

• Variable data modified by a built-in DS2 package. For example, if the HASH.FIND method modifies a data variable, this variable modification is not reported in the trace.
• Implicit updates of DS2 automatic variables. For example, the implicit incrementing of the N automatic variable is not reported in the trace.
• Implicit initialization of variables to missing or null during variable creation.
• Implicit reinitialization of nonretained variables to missing or null before each iteration of the RUN method.

The default format for the data type of the variable is used to convert noncharacter values to a character representation for reporting in a trace. If a format has been associated with a variable either by a HAVING clause, a SET statement, or a MERGE statement, the associated format is not used to format the variable data value for reporting in a trace. The character representation of a data value is truncated to 10,485,760 characters when reporting the data value in a trace.

The messages in the trace report the type and name of the program block containing the statement, the line number of the statement in the SAS^® log (n1), the line number of the statement offset from the first line of the program block (n2), and the variable name and value. Here is the format for a trace message:

Here is an example:

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Operating System and Release Information

proc ds2;
ds2_options tracevariables;
package swapper / overwrite=yes;
  method swap(in_out double x, in_out double y);
    dcl double t;
    t = x;
    x = y;
    y = t;
  end;
endpackage;

ds2_options tracevariables;
data _null_;
  method init();
    dcl package swapper s();
    dcl double a[2];
    a := (10, 20);
    put 'before swap:' a[*]=;
    s.swap(a[1], a[2]);
    put 'after swap:' a[*]=;
  end;
enddata;
run; 
quit;

Here are log messages reported to the SAS logging facility for the App.TableServices.DS2.Runtime.TraceVariables logger:

2021-01-12T13:33:35,063 TRACE [00000007] - Line 17 (data block line 5): a[1]=10
2021-01-12T13:33:35,063 TRACE [00000007] - Line 17 (data block line 5): a[2]=20
2021-01-12T13:33:35,063 TRACE [00000007] - Line 6 (package swapper line 4): t=10
2021-01-12T13:33:35,064 TRACE [00000007] - Line 7 (package swapper line 5): x=20
2021-01-12T13:33:35,064 TRACE [00000007] - Line 8 (package swapper line 6): y=10

Viya on Linux: An update for this issue is available for SAS Viya 3.5. For instructions on how to access and apply software updates, see the Updating Your SAS Viya software section in the SAS Viya 3.5 for Linux Deployment Guide at