I had to add a new build target for the "scratch.hs" file so I could
write simple test programs for debugging purposes. Since updating to GHC
7.8.2 GHCi has refused to compile Dao because of corrupted .dyn_hi files
in my GHC global package repository for packages that Dao depend on.
Bug fix: the instantiation of 'Dao.Interpreter.Reference' into the
'Prelude.Read' class, which is used to cast a string value to a
reference value, was broken. This has been fixed. Also the built-in Dao
programming language function "ref()" creates a
'Dao.Interpreter.RefWrapper' value, rather than a straight
'Dao.Interpreter.Reference' value.