Document the intricacies of ForallC variable quantification better
authorRyan Scott <ryan.gl.scott@gmail.com>
Sat, 2 Sep 2017 19:32:56 +0000 (15:32 -0400)
committerRyan Scott <ryan.gl.scott@gmail.com>
Sat, 2 Sep 2017 19:32:57 +0000 (15:32 -0400)
commit6330b0b0938bc7b27463b3bbfa0df661e4a966b1
tree89962f2318c4d843e640b18d3a4e29e4b6517996
parent590e7376de357a61555181d78f5201cf2f503aa5
Document the intricacies of ForallC variable quantification better

Summary:
I recently (re-)discovered that `ForallC` quantifies different type variables
depending on whether `GadtC` is present or not. This is an important
enough gotcha where I feel like this fact should also be advertised in the
`template-haskell` documentation itself, so this patch does just that.

Test Plan: Read it

Reviewers: goldfire, austin, bgamari

Subscribers: rwbarton, thomie

GHC Trac Issues: #13885

Differential Revision: https://phabricator.haskell.org/D3880
libraries/template-haskell/Language/Haskell/TH/Syntax.hs