Learning the XML example fails in constructChecks
Created by: karl
λ> learnLanguage "<a>hi</a>" xml
_exception = GHC.Exception.Type.SomeException
(GHC.Exception.ErrorCallWithLocation
"constructChecks comparing incompatible langs:
[<a>hi</a>|alt]
([<|rep]+[a>hi</a>|alt])
"
"CallStack (from HasCallStack):
error, called at /home/karl/w/glade-haskell/src/Lib.hs:110:3 in main:Lib")