In electronic design the diagram is a 'schematic' and the text is a 'netlist'. Open source code, which is almost all not perl, is at Open Collector.

There are tools to extract netlists, compare netlists, check for errors (eg outputs connected to outputs), etc.

It would be great to build a netlister and schematic drawing program, and also create tools to build a library of graphical symbols. An online database to instantiate the symbols into the schematic is also a great tool.

Perl is a great language for building this type of system. Your example shows a grammar, but you could also make a regular expression builder or an electronic design system.

One would think that Visio might be good at this sort of thing, but it is lame in this respect.