Evan Relf evanrelf

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.

How to get in touch with your emotions

I wanted to share something I've learned in the course of therapy that I felt might benefit others. Specifically, I'd like to share how to better listen to one's emotions.

Why should we do this?

You might wonder why would we want to be in better touch with our emotions. One reason why is that everybody builds a metaphor or narrative for themselves

Portland recommendations by Sam

Sorted by location-ish. I tried to reduce the list to places I think are good for visitors vs. my absolute favorites, but I put a section at the bottom for places that may not be for everyone.

Breakfast / Brunch

Toki Restaurant (Downtown)

580 SW 12th Ave

My order: Grilled mackerel breakfast with a bloody mary. Their Dalgona coffee is quite good too.

	-- 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.
	--

	module Main where

	import Prelude

	import Data.Symbol (class IsSymbol)
	import Prim.Row as Row
	import Prim.RowList as RowList
	import Record as Record
	import Type.Proxy

	THIS GIST IS OUT OF DATE! Please use my new project template here to get started with Zig on Playdate:
	https://github.com/DanB91/Zig-Playdate-Template


	The rest of this is preservied for historical reasons:


	This is a small snippet of some code to get you started for developing for the Playdate on Zig. This code should be used as a starting point and may not compile without some massaging. This code has only been tested out on macOS and you'll need to modify the addSharedLibrary() portion of build.zig to output a .dll or .so instead of a .dylib, depending on you platform.

	This code will help you produce both an executable for the Playdate simulator and also an executable that actually run on the Playdate hardware.

	let
	# Playdate distributes their SDK as precompiled x86_64 binaries
	# currently so we have to import cross-compiled packages for it
	# if we're not on an x86_64 system.
	pkgsIntel = import <nixpkgs> {
	crossSystem = {
	config = "x86_64-unknown-linux-gnu";
	};
	};
	in

	{-# LANGUAGE RankNTypes #-}
	{-# LANGUAGE ScopedTypeVariables #-}
	{-# LANGUAGE DataKinds #-}
	{-# LANGUAGE PolyKinds #-}
	{-# LANGUAGE TypeFamilies #-}
	{-# LANGUAGE UndecidableInstances #-}
	{-# LANGUAGE TypeApplications #-}
	{-# LANGUAGE TypeOperators #-}
	{-# LANGUAGE AllowAmbiguousTypes #-}
	{-# LANGUAGE FunctionalDependencies #-}

	// This is free and unencumbered software released into the public domain.

	// Anyone is free to copy, modify, publish, use, compile, sell, or
	// distribute this software, either in source code form or as a compiled
	// binary, for any purpose, commercial or non-commercial, and by any
	// means.

	// In jurisdictions that recognize copyright laws, the author or authors
	// of this software dedicate any and all copyright interest in the
	// software to the public domain. We make this dedication for the benefit