foreach is often used with single element as a convenient method of both setting $_ and providing a block in which last can be used.

As for your problem, the code is equivalent to:

 foreach --+   +-- first iteration
           |   |
           v   v
print( (@$res)[0]->[0], "\n");
       ----------
            |
            +-- What $_ contained

[download]

or just:
print "$res->[0][0]\n";

In reply to Re:Array Deferencing Question by ikegami
in thread Array Deferencing Question by Anonymous Monk

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