Taylor Fausak tfausak

## ios-8-web-app.html
<!doctype html>

<!-- http://taylor.fausak.me/2015/01/27/ios-8-web-apps/ -->

<html>
  <head>
    <title>iOS 8 web app</title>

    <!-- CONFIGURATION -->

## claude-status-line.sh
#!/usr/bin/env sh
# https://code.claude.com/docs/en/statusline

json=$( cat )

directory=$( basename "$( printf '%s' "$json" | jq --raw-output .workspace.current_dir )" )

branch=$( git --no-optional-locks symbolic-ref --short HEAD 2>/dev/null || printf null )

model=$( printf '%s' "$json" | jq --raw-output .model.id )

## Main.hs
#!/usr/bin/env cabal
{- cabal:
build-depends: base, directory, process
ghc-options: -Wall
-}

-- https://gitlab.haskell.org/ghc/ghc/-/issues/27130

import qualified Control.Exception as Exception
import qualified Control.Monad as Monad

## bench_generics_unified.sh
#!/usr/bin/env bash
# Unified Generic deriving benchmark
# Tests compile-time (allocations + time) and runtime (to . from round-trip)
# for record types (N fields) and sum types (N constructors),
# comparing -fdirect-core-generic-deriving vs -fno-direct-core-generic-deriving.
set -euo pipefail

GHC="${GHC:-./_build/stage1/bin/ghc}"
OPT="${OPT:--O0}"

## invertible-syntax-descriptions.markdown

      
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                tfausak
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                Survey of invertible syntax description libraries for Haskell.
              
          
    Invertible syntax descriptions

An "invertible syntax description" is something that can be used to both parse and generate a syntax.
For example, instead of defining separate toJson and fromJson functions for a given data type, an invertible syntax description could be used to provide both.
There are many Haskell libraries that provide this functionality or something close to it.
As far as I can tell most of them are at least inspired by Invertible syntax descriptions by Tillmann Rendel and Klaus Ostermann.
Personally I am interested in using these for HTTP routing.
I frequently want to be able to define a route such as /episodes/:id.json, dispatch based on that route, and generate links to that route.
Doing so manually is tedious and error prone.

  
## balatro-daily-seed.hs
#! /usr/bin/env cabal
{- cabal:
build-depends: base, random, time
-}
import qualified Data.Time as Time
import qualified System.Random as Random

main :: IO ()
main =
  putStrLn

## Witch.hs
{-# LANGUAGE DeriveGeneric #-}
{-# LANGUAGE DerivingVia #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE StandaloneDeriving #-}
{-# LANGUAGE TypeOperators #-}
{-# LANGUAGE UndecidableInstances #-}

## UUIDv7.hs
#! /usr/bin/env cabal
{- cabal:
  build-depends:
    base,
    bytestring,
    entropy,
    tasty-bench,
    time,
    uuid,
  ghc-options:

## buoy.hs
-- This whole thing is shamelessly stolen from:
-- <https://doisinkidney.com/snippets/nary-uncurry.html>.

-- Without flexible instances, GHC complains about the `HasApply` instances:
--
-- > Illegal instance declaration for `HasApply a Z`. All instance types must
-- > be of the form `(T a1 ... an)` where `a1 ... an` are *distinct type
-- > variables*, and each type variable appears at most once in the instance
-- > head.
--

## normalize-csv.hs
#!/usr/bin/env stack
-- stack --resolver lts-8.6 --install-ghc script
import Data.ByteString
import Data.Conduit
import Data.Conduit.Binary
import Data.CSV.Conduit
import System.IO

main = transformCSV
  defCSVSettings
	<!doctype html>

	<!-- http://taylor.fausak.me/2015/01/27/ios-8-web-apps/ -->

	<html>
	<head>
	<title>iOS 8 web app</title>

	<!-- CONFIGURATION -->
	#!/usr/bin/env sh
	# https://code.claude.com/docs/en/statusline

	json=$( cat )

	directory=$( basename "$( printf '%s' "$json" \| jq --raw-output .workspace.current_dir )" )

	branch=$( git --no-optional-locks symbolic-ref --short HEAD 2>/dev/null \|\| printf null )

	model=$( printf '%s' "$json" \| jq --raw-output .model.id )
	#!/usr/bin/env cabal
	{- cabal:
	build-depends: base, directory, process
	ghc-options: -Wall
	-}

	-- https://gitlab.haskell.org/ghc/ghc/-/issues/27130

	import qualified Control.Exception as Exception
	import qualified Control.Monad as Monad
	#!/usr/bin/env bash
	# Unified Generic deriving benchmark
	# Tests compile-time (allocations + time) and runtime (to . from round-trip)
	# for record types (N fields) and sum types (N constructors),
	# comparing -fdirect-core-generic-deriving vs -fno-direct-core-generic-deriving.
	set -euo pipefail

	GHC="${GHC:-./_build/stage1/bin/ghc}"
	OPT="${OPT:--O0}"
	#! /usr/bin/env cabal
	{- cabal:
	build-depends: base, random, time
	-}
	import qualified Data.Time as Time
	import qualified System.Random as Random

	main :: IO ()
	main =
	putStrLn
	{-# LANGUAGE DeriveGeneric #-}
	{-# LANGUAGE DerivingVia #-}
	{-# LANGUAGE FlexibleContexts #-}
	{-# LANGUAGE FlexibleInstances #-}
	{-# LANGUAGE MultiParamTypeClasses #-}
	{-# LANGUAGE ScopedTypeVariables #-}
	{-# LANGUAGE StandaloneDeriving #-}
	{-# LANGUAGE TypeOperators #-}
	{-# LANGUAGE UndecidableInstances #-}
	#! /usr/bin/env cabal
	{- cabal:
	build-depends:
	base,
	bytestring,
	entropy,
	tasty-bench,
	time,
	uuid,
	ghc-options:
	-- This whole thing is shamelessly stolen from:
	-- <https://doisinkidney.com/snippets/nary-uncurry.html>.

	-- Without flexible instances, GHC complains about the `HasApply` instances:
	--
	-- > Illegal instance declaration for `HasApply a Z`. All instance types must
	-- > be of the form `(T a1 ... an)` where `a1 ... an` are *distinct type
	-- > variables*, and each type variable appears at most once in the instance
	-- > head.
	--
	#!/usr/bin/env stack
	-- stack --resolver lts-8.6 --install-ghc script
	import Data.ByteString
	import Data.Conduit
	import Data.Conduit.Binary
	import Data.CSV.Conduit
	import System.IO

	main = transformCSV
	defCSVSettings