gEDA-dev: Diode symbols in GSchem and PCB

[DJ Delorie]

> I fail to understand what is wrong with our current, simple
> implementation.

Making our implementation simple...

> Yes, there are issues with some pin numbers in the symbol lib, but
> it is incumbent upon all users to verify that the pin numbering of
> the symbol matches that of the actual part!

... makes doing that harder.

> The user *must* read the datasheet.  The user is supposed to be an
> engineer, right?

In most "real companies" there are three "users" involved.  One reads
the data sheets and makes the official symbols and footprints.  The
second creates the schematics from said symbols.  The third does the
layout from said footprints.

This works because there's a huge database mapping the symbols,
footprints, and part numbers to each other.  We don't have that.

Thus, *our* way involves reading the spec sheet *every time*.  We have
no mechanism for caching this information, other than to create a
unique symbol/footprint for each part number, resulting in hundreds of
diodes, dozens of NAND gates, millions of resistors, etc.

There's a break even point where the complexity of our implementation
balances the complexity of the user's experience.  I think we're close
to, if not past, that point.