Multiple defined in authz_svn_module

Dears,

  What is the result of multiple defined permission?
  Is it an OR operation toward write permission?
  Does the order matter?

  In the below 3 cases, A can write the directory1.
  However, in case 1 & 2, we want A have write-permission, but
  in case 3, A is planned to have no permission.

  There is no detail explanation in the Subversion book.

  Case 1:
   [groups]
    G1 = A, B, C
    G2 = A

   [project:/directory1]
   @G1 = r
   @G2 = rw

  Case 2
   [groups]
    G1 = A, B, C

   [project:/directory1]
   @G1 =
   A = rw

  Case 3
   [groups]
    G1 = A, B, C

   [project:/directory1]
   @G1 = rw
   A =

--
Jing-Reng Huang