Detect or warn when sort is needed or assummed

[dwhollick]

/* summarize sashelp.class with one row per age and a variable called "namelist" containing a comma delimited list of names */
Select Generate Code.

The generated DATA step logic is correct but will not run as-is because the input data set is not sorted by AGE. The system should check if the dataset is already sorted by age or if an index is defined on age. If not, it should add a proc sort to the generated code.

Or, at a minimum, the user should be warned that the generated code assumes a sorted order.

data summarized_class;
set sashelp.class;
by age;
length namelist $200;
retain namelist;

if first.age then namelist = name;
else namelist = catx(",", namelist, name);

if last.age then output;
drop name;

format namelist $200.;
run;