[exim] acl example

Could some one give me an example acl for white listing that could be
placed at the top of my alc's
I tried some thing like

whitelist:
accept senders = lsearch*@;/usr/local/etc/exim/test

And a few others off the mailing list with no success.
I would love to include some like
sender_domains = /usr/local/etc/exim/exim.whitelist
senders = /usr/local/etc/exim/exim.whitelist2

Once i have got round that problem then i will be happy.
At the moment i have thee above lines in all the acl's. Which works fine
but i would like it in one place. Just a few clues or pointers would be
great help.
I asked a similar question in a previous post and Andrea was kind enough
to explain how acl's work. But the syntax of it eludes me.
Terry.