The author of this project emailed me after reading my ealier comments about ASCII UML. It is an "ASCII UML class diagram interpreter and sourcecode translation engine". I haven't tried to use it, but this is an example of what the UML looks like:

[Human]<|--+--[Woman]<>-- +mother +child {0..*} --[Human]
           \--[Man]<>-- +father +child {0..*} --[Human]