% perl -le '$_ = ($x) = (4, 5, 6); print'
3

##</code><code>##

% perl -MO=Deparse,-p -le '$_ = ($x) = (4, 5, 6); print'

($_ = ($x = (4, 5, 6)));
print($_);

-e syntax OK

##</code><code>##

% perl -le '($_ = ($x = (4, 5, 6))); print($_)'
6