for almost all other external nodes (notable exception "txl")
src/spicelib/devices/*/*def*.h, declare external node variables const
1) The compiler shall emit an error message if we still mess around
with external node numbers.
2) To mark which elements of the instance struct are meant to be set
externally when parsing the netlist
These "external" node variables are exclusively set via the
overlay struct GENinstance, member GENnode[]
We shall not mess around with these "external" node variables
because it would get rather difficult to avoid bugs considering
re-invocation of the XXXsetup() routine.
This gets interesting for devices with optional ports,
which get copied around depending on the amount of connected ports.
rlar
Henrik Forsten
Francesco Lannutti
pnenzi