ABAP关键字SUBMIT AND RETURN的学习

PARAMETERS: in TYPE int4 OBLIGATORY.

WRITE:/ 'Hello', in.

Launcher

REPORT z.

DATA: rspar TYPE TABLE OF rsparams.

DO 12 TIMES.
  CLEAR: rspar.
  rspar = VALUE #( ( selname = 'IN'
                      sign = 'I'
                      option = 'EQ'
                      low = sy-index ) ).
  SUBMIT zlock1 WITH SELECTION-TABLE rspar AND RETURN.
ENDDO.

WRITE:/ 'OK'.

Test result

Hello 1,2,… 12, then ok
IF “AND RETURN” is commented out, all other variant within DO will not have any chance to execute at all.
Cannot observe this assertion failed in ST22: