Some questions about netboot

[Soos Arpad <qwer@vienna.at>]

<recipe>::=<header>_<partitions>
<header>::=<simple name>|<debconf name>
<simple name>::=<name>_:
<name> can be for example "Multi user system".
<debconf name>::=<debconf template>_::

in /usr/share/doc/debian-installer/devel/partman-auto-recipe.txt and even

<partitions>::=<partition>|<partition>_<partitions>
<partition>::=<limits>_<specifiers>_.
<limits>::=<minimal size>_<priority>_<maximal size>_<parted fs>

the rules are not at all respected in the example.
I wonder how it really works as I don't can calculate
it for my special need.

What ist the program doing the patitioning?

Thanks!
Arpad