$ perl a.pl
1..30
ok 1
ok 2
ok 3
ok 4
ok 5
ok 6
ok 7
ok 8
ok 9
ok 10
ok 11
ok 12
ok 13
ok 14
not ok 15
#   Failed test at a.pl line 71.
#                   ''
#     doesn't match '(?-xism:^Attribute \(union\) does not pass the type constraint)'
not ok 16
#   Failed test at a.pl line 71.
ok 17
ok 18
ok 19
ok 20
ok 21
ok 22
ok 23
ok 24
ok 25
ok 26
ok 27
ok 28
not ok 29
#   Failed test at a.pl line 82.
#                   ''
#     doesn't match '(?-xism:^Attribute \(union\) does not pass the type constraint)'
ok 30
# Looks like you failed 3 tests of 30.