/\$\[/ # Comment on same line as meaningful content.
# Lack of whitespace between regex and message intentional.
/\$SIG\{__DIE__\}/Do not use $SIG{__DIE__}. Use END{} or override CORE::GLOBAL::die() instead.
# Extra leading and trailing whitespace here is intentional.
/\$\^S/ Found use of $^S. You should seriously consider what your code is trying to do.