Debug printing inside the typechecker knot

Fri Apr 5 13:21:00 UTC 2019

> Did you mean "What is the TcHsSyn counterpart to TcMType.zonkTcTyVar"?

D'oh. Yes, I did.

> But it's never a bad idea to document more.

I've documented all the wisdom from here in this wiki page [1]! Feel
free to edit it if there are any corrections to be made.

Ryan S.
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[1] https://gitlab.haskell.org/ghc/ghc/wikis/commentary/compiler/tying-the-knot/printing