Reverse-references in protocol error documentation

[plaidfinch]

In the documentation for the protocol, we will (shortly) have lists of possible errors for each available method, which link to a central list of all errors in the protocol. However, it would be likewise nice to have each error in the central list be associated with a list of links back to each of the methods which could throw it.

As far as I can tell, this would require one of:

1. the master list of all errors being generated programmatically from the documentation of all the methods
   • Pros:
     • when adding new methods in the future, you only need to edit one file
   • Cons:
     • grouping errors in the master list into a logical organization more complex than "sorted by error code" would require some kind of tagging or templating
2. the links to possible errors in each method's documentation being inserted programmatically, as determined by the master list of all errors
   • Pros:
     • the master list of errors, being a static page, can be organized as makes the most logical sense, albeit with some kind of tagging to note the location of each error to be extracted
   • Cons:
     • editing or adding a new method requires remembering to change two files
3. Potentially there is some Sphinx-specific way to insert reverse references via special markup, rather than by generating/pre-processing reST files ourselves?