The HiPi modules for Perl provide examples of Perl usage with the GPIO and peripherals of the Raspberry Pi.
The HiPi modules are written for the system Perl on the latest offical Rasbian Jessie release. Older Raspbian releases may still work.
The distribution includes the bcm2835 library source from Mike McCauley which is wrapped in the module HiPi::BCM2835
The wiringPi library from Gordon Henderson is used by the module HiPi::Wiring