Element Discard Variable
Element Discard variables act as placeholders and are intentionally not allocated. Element Discard variables can be used in the 'SET' SFCodeBlock any time the expression result is not to be stored, for example, if you don't need to store the result of a Built-in function.
Example:
_= TableInsert($$myTable; 'Column1'; Material; 'Column2'; o_rec_mass; 'Column3';
The TableInsert function is executed per each element, and inserts a
record per each Element with the value of the attributes Material and o_rec_mass.