rengolin/HPCC-Platform — comment on commit bdc2c1ae7b0c1ea75c733e720c30646df1712e78
File: ecl/regress/dataset_transform.ecl line 50
By ghalliday:

This isn't actually a variable case.
C := 5 is a definition, not an assignment.
You need something like
C := 5 : stored('C');
to force it to a run time variable.