-- rather like the free variables of the program, but
-- are implicit instead of explicit.
+ tcg_th_used :: TcRef Bool, -- True <=> Template Haskell syntax used
+ -- We need this so that we can generate a dependency on the
+ -- Template Haskell package, becuase the desugarer is going to
+ -- emit loads of references to TH symbols. It's rather like
+ -- tcg_inst_uses; the reference is implicit rather than explicit,
+ -- so we have to zap a mutable variable.
+
-- Now a bunch of things about this module that are simply
-- accumulated, but never consulted until the end.
-- Nevertheless, it's convenient to accumulate them along