mgsloan

04785022ed95f0901f865f17542134a3fe9c70cf034cb3eda5e170417372e2abd9e972c6462cfe9b68fa340db25ccaf6d50cc024da358d883e0e15e8cea5a2ec

mgsloan

{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE MultiParamTypeClasses #-}

-- https://gist.github.com/mgsloan/7100f55c6ec12be8776a1a1c347cf963
-- for a more complex version with better type inference.
--
-- It was initially surprising to me that this one doesn't need the
-- "closed type family" trick to direct which instance is used. On
-- further thought,

mgsloan

{-# LANGUAGE DataKinds #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TypeApplications #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE UndecidableInstances #-}

import Data.Proxy (Proxy(..))

mgsloan

.roam_navigator_hint {
  color: purple !important;
  font-size: 20px !important; 
}

.roam_navigator_hint_typed {
  color: orange !important;
}

.roam-sidebar-container .roam_navigator_hint, #right-sidebar .roam_navigator_hint {

mgsloan

#!/bin/sh -e

# Script I wrote before I realized
# https://github.com/MatthieuBizien/roam-to-git exists

if [ "$#" -eq 1 ]; then
    LAST_ROAM_EXPORT=$1
elif [ "$#" -eq 0 ]; then
    echo "Attempting to use XDG info to find roam export."
    # Load XDG dir configuration into variables

mgsloan

ErrorMonoidMaybeInt.hs:12:3-48: Splicing declarations
    explainInstanceError [t| Monoid (Maybe Int) |]
  ======>
    main_a6aM
      = putStrLn
          (displayInst
             (resolveMonoid (Data.Proxy.Proxy :: Data.Proxy.Proxy (Maybe Int))))
    class Semigroup_ a_a4Ra => Monoid_ (a_a4Ra :: GHC.Types.Type) where
      resolveMonoid :: Data.Proxy.Proxy a_a4Ra -> Inst
    instance OVERLAPPABLE #-} base-4.12.0.0:Data.Typeable.Internal.Typeable a_a4Ra =>

mgsloan

-- Context: https://github.com/ghc-proposals/ghc-proposals/pull/273#issuecomment-530215302

{-# LANGUAGE ExistentialQuantification #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE GADTs #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TypeOperators #-}
{-# LANGUAGE UndecidableInstances #-}

import Data.Typeable

mgsloan

Context: ghc-proposals/ghc-proposals#273 (comment)

I have not reviewed this proposal thoroughly, however I would really like this feature and have considered proposing it in the past. To make this more clearly defined and understandable for users, I'd like to propose a simple rule for what is allowed:

Local types could desugar to top level declarations

My intuition says that if this holds true then the feature becomes much easier to implement than if it does not. As far as I can tell this rule is mostly already followed in the proposal. Specifically:

All instances remain (conceptually) global, but they may involve local types and values

mgsloan

diff --git a/src/RIO.hs b/src/RIO.hs
index e4e2c66..e071714 100644
--- a/src/RIO.hs
+++ b/src/RIO.hs
@@ -1,3 +1,4 @@
+-- | This mo
 module RIO
   ( module RIO.Prelude.Display
   , module RIO.Prelude.Extra
diff --git a/src/RIO/Prelude/Reexports.hs b/src/RIO/Prelude/Reexports.hs

mgsloan

Keybase proof

I hereby claim:

• I am mgsloan on github.
• I am mgsloan (https://keybase.io/mgsloan) on keybase.
• I have a public key ASD0wSGDjAfr3397iicKObFGTTGmQyUVookmyd7W7GdH-go

To claim this, I am signing this object: