question: public static void processRemoveVariableInstruction ( ExecutionContext ec , String varname ) throws DMLRuntimeException { Data input1_data = ec . removeVariable ( varname ) ; if ( input1_data == null ) throw new DMLRuntimeException ( "Unexpected error: could not find a data object for variable name:" + varname + ", while processing rmvar instruction." ) ; if ( input1_data instanceof MatrixObject ) { ec . cleanupMatrixObject ( ( MatrixObject ) input1_data ) ; } }
target:  Remove variable instruction externalized as a static function in order to allow various  cleanup procedures to use the same codepath as the actual rmVar instruction