jkarni

#!/usr/bin/env nix-shell
#!nix-shell -i runhaskell -p "haskellPackages.ghcWithPackages (pkgs: with pkgs; [servant-server servant-auth-server servant-streaming-server ])"
#!nix-shell -I nixpkgs=https://github.com/NixOS/nixpkgs/archive/299814b385d2c1553f60ada8216d3b0af3d8d3c6.tar.gz

{-# LANGUAGE DataKinds                  #-}
{-# LANGUAGE DeriveGeneric              #-}
{-# LANGUAGE FlexibleInstances          #-}
{-# LANGUAGE FunctionalDependencies     #-}
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE LambdaCase                 #-}

jkarni

{-# LANGUAGE Arrows                 #-}
{-# LANGUAGE ConstraintKinds        #-}
{-# LANGUAGE FlexibleContexts       #-}
{-# LANGUAGE FlexibleInstances      #-}
{-# LANGUAGE FunctionalDependencies #-}
{-# LANGUAGE GADTs                  #-}
{-# LANGUAGE KindSignatures         #-}
{-# LANGUAGE MultiParamTypeClasses  #-}
{-# LANGUAGE NoImplicitPrelude      #-}
{-# LANGUAGE OverlappingInstances   #-}

jkarni

==================== Tidy Core ====================
Result size of Tidy Core
  = {terms: 186, types: 1,481, coercions: 3,686}

-- RHS size: {terms: 2, types: 0, coercions: 0}
$s$fShowBook'7 :: [Char]
[GblId,

 Unf=Unf{Src=<vanilla>, TopLvl=True, Value=False, ConLike=False,
         WorkFree=False, Expandable=False, Guidance=IF_ARGS [] 40 0}]

jkarni

{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE DataKinds #-}
{-# LANGUAGE TypeOperators #-}
{-# LANGUAGE StandaloneDeriving #-}

module Realm.Newrelic where

import Control.Monad.Trans.Either

import Data.Proxy

jkarni

{
  "paths": {
    "/user/{username}": {
      "put": {
        "parameters": [
          {
            "type": "string",
            "name": "username",
            "in": "path",
            "required": true

jkarni

{-# LANGUAGE CPP                        #-}
{-# LANGUAGE DataKinds                  #-}
{-# LANGUAGE DeriveFoldable             #-}
{-# LANGUAGE DeriveFunctor              #-}
{-# LANGUAGE DeriveGeneric              #-}
{-# LANGUAGE DeriveTraversable          #-}
{-# LANGUAGE FlexibleInstances          #-}
{-# LANGUAGE FunctionalDependencies     #-}
{-# LANGUAGE GADTs                      #-}
{-# LANGUAGE GeneralizedNewtypeDeriving #-}

jkarni

#!/usr/bin/env stack
-- stack --resolver nightly-2015-10-08 runghc --package monadio-unwrappable-0.3
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE TypeFamilies #-}

import Control.Monad
import Control.Monad.Trans.Class
import Control.Monad.IO.Class
import Control.Monad.Trans.Control
import Control.Monad.Trans.Except

jkarni

{-# LANGUAGE ConstraintKinds #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# OPTIONS_GHC -fdefer-type-errors #-}
module Main where

import Data.Constraint
import Control.Exception
import System.IO.Unsafe

show' y = unsafePerformIO $ do

jkarni

{-# LANGUAGE ConstraintKinds #-}
module Main where

import Data.Constraint

show' :: (Maybe (Dict (Show a))) -> a -> String
show' (Just Dict) x = show x
show' Nothing    _ = "<<not showable>>"

t1 = show' (Just Dict) 5

jkarni

-- first a separate class to interpret the access/permission DSL 
class IsAccess a where
   getAccess :: Proxy a -> Id -> Bool 
   -- ^ probably something quite different here. The two main options I see generally
   -- are evaluating to some normal form (like AccessType) and not requiring Id, or 
   -- having Id and then directly evaluating to Bool
   -- If you want to be allowed to require other values depending on the type (which I
   -- think you do) you'd need an associated type synonym).

instance (IsAccess a, IsAccess b) => IsAccess (a :|| b) where