That's usually not what you want: that'll give you three copies of the same arrayref, so if you later modify an element in one row it'll modify it in all rows:

% perl -wle '@aoa = ([(1) x 3]) x 3; $aoa[1][2] = 3; print "@$_" for @
+aoa'
1 1 3
1 1 3
1 1 3
[download]

If you want each element to be independent, a typical approach is to pass it through map:

% perl -wle '@aoa = map [(1) x 3], 1..3; $aoa[1][2] = 3; print "@$_" f
+or @aoa'
1 1 1
1 1 3
1 1 1
[download]