Block ALV Report Doubt!

Hi!

In Block AlV we r using Fun Mod

REUSE_ALV_BLOCK_LIST_APPEND

To display data in blocks and called again to display other data in block in same screen.

I want to know REUSE_ALV_BLOCK_LIST_DISPLAY Fun mod is optional or mandatory

without using this also shall i get the required o/p.

Looking for your reply.

Rahul.