Lets see an example, how recursive dep files look in 2.10 I will use hal.tcz as an example.
The old fashioned hal.tcz.dep file lists all extensions rerquired:
expat2.tcz
glib2.tcz
dbus.tcz
dbus-glib.tcz
libpci.tcz
pci-utils.tcz
libusb.tcz
usb-utils.tcz
udevadm.tcz
acl.tcz
The new hal.tcz.dep is:
dbus-glib.tcz
pci-utils.tcz
usb-utils.tcz
udevadm.tcz
libpci.tcz and libusb.tcz are listed in pci-utils.tcz.dep and usb-utils.tcz.dep therefore no need for them here, will be loaded by appbrowser due to pci-utils.tcz.dep and usb-utils.tcz.dep Similarly expat2.tcz, glib2.tcz and dbus.tcz will be loaded due to dbus-glibc.tcz.dep; acl.tcz is also removed as it is a dependency of udevadm.
Now hal.tcz.dep is more informative, as it lists only the real dependencies.