Attribute parameter substitution patches

[vzh]

gnetlist-parameter-substitution.tar.gz

(This is launchpad bug https://bugs.launchpad.net/geda/+bug/911440)

Stephan Böttcher writes:

here's a patch to gnetlist that implements parameter substitution in
hierarchical schematics. The idea is that some attribute values in the
child page are defined in terms of parameters, that can be substituted
in individual instances.

A resistor in the sub-schematic may have the attribute

value=$RFB

and the instance symbol for that sub-scematic in tha parent schematic
may have the attibute

parameter=RFB:12k

He continues:

a extension of the previous patch to allow parameter names to contain
digits, and allow references to arbitrary parameter names in ${braces}.