perl -le '$data=[{ data => 1 },{a => 2, b => 3}];print $$data[0]->{data}'
1


##</code><code>##

 perl -wle '$data=[{ data => 1 },{a => 2, b => 3}];print $$data[1]->{c}'
Use of uninitialized value in print at -e line 1.