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Fibers

Fibers are an abstraction over sequential computation, similar to threads but at a higher level. There are two ways to think about this model: by example, and abstractly from first principles. We'll start with the example.

(credit here is very much due to Fabio Labella, who's incredible Scala World talk describes these ideas far better than I can)

Callback Sequentialization

Consider the following three functions

Cats Anchored

cats-time

Cats Instances for Java Time

cats-scalacheck

Cats Instances for Scalacheck

All the docs probably

base..

.> view base..

  (base..) : (b ->{𝕖} c) -> (a ->{𝕖} b) -> a ->{𝕖} c
  (base..) f g x = f (g x)

Quick PSA on Metals with vscode

Since scala changes a lot of files in build and vscode watches those files. It actually has quite a delay. Adding this to settings will improve performance by an enormous degree. Especially on larger projects.

"files.exclude": {
        "**/.bloop": true,
        "**/.metals": true,
 "**/target": true

Haskeller Competency Matrix

See also List of materials about Software Design in Haskell

	Junior	Middle	Senior	Architect
Haskell level	Basic Haskell	Intermediate Haskell	Advanced Haskell	Language-agnostic
Haskell knowledge scope	Learn you a Haskell	Get programming with Haskell	Haskell in Depth	Knows several languages from different categories
	Get programming with Haskell	Haskell in Depth	Functional Design and Architecture
	Soar with Haskell	[Soar

Frieldly optics name proposals

Here are some proposal for optics names. The goal is to give a better intuition to beginners, especially people with no FP experience.

Setter -> Replace, Modify, Write
Fold -> Aggregate
NonEmptyFold -> Reduce
Getter -> Read
ReadOnlyOptional -> ???

Tezos Token Tantrum

2020, Feb 14

This is a companion code sample to go with the Tezos is now an asset tokenization platform article on Medium from The Cryptonomic Aperiodical. As always, to test this code get infrastructure access from Nautilus Cloud.

Purpose

The code included here demonstrates token deployment and management workflows. It does not have an example for burn(), but that is also available in the API.

Optics By Example Cheat Sheets

The following are appendices from Optics By Example, a comprehensive guide to optics from beginner to advanced! If you like the content below, there's plenty more where that came from; pick up the book!

Operators
Composition Guide
Substitution Guide
Optical Constarints and Types

Operator Cheat Sheet

Since macOS Catalina, the root drive is read-only. The solution is to create a separate APFS volume and a “synthetic” /nix directory which points to it:

# Check if /nix exists, if not:
echo 'nix' | sudo tee -a /etc/synthetic.conf
# this will create a "synthetic" empty directory /nix

# REBOOT so macOS sees the synthetic directory

# After rebooting, create an APFS volume for Nix

	#!/usr/bin/env python3

	"""Set iTerm2 color preset according to macOS theme.

	Requires iTerm2 version 3.3 or newer.

	Save as ~/Library/ApplicationSupport/iTerm2/Scripts/AutoLaunch/sync_theme.py and
	enable under scripts menu in iTerm2.
	"""