algal

/*:
 
 Paste this into Swift Playgrounds on an iPad to see how
 modifying a label's frame affects its intrinsicContentSize.
 
 As near as I can tell, frame currently does not affect
intrinsicContentSize.

At least I am sure it did not used to affect it.
 

algal

Setting up a Jupyter server

These notes describe how to install and configure a secured Jupyter server directly onto Ubuntu 16.04.

Warning: this might be stupid. In 2017, it might be wiser just to grab a docker image, since some of these look extremely well-packaged. In my view, the advantage of docker is that someone else does the packaging, while docker itself provides cross-platform portability, rudimentary process supervision, and perhaps a simpler model than your OS's package manager. It is easy to know what is installed, how to uninstall it, and where its boundaries are. The disadvantage of docker is that you need to understand docker possibly in addition to understanding some Unix fundamentals.

Setup LetsEncrypt certs if needed

Install LetsEncrypt

algal

#!/bin/sh
emacsclient -n -e "(find-file-other-frame \"$1\")"

# For this script to work, you must already have started
# an emacs instance and started its server. You can do 
# that by adding some elisp like the following into
# your .emacs file:
#
#   (require 'server)
#   (server-mode 1)

algal

//: Known-Good: Version 9.0 beta 5 (9M202q)

//: Playground - noun: a place where people can play



import UIKit


//: This playground is for generating code to define CGColors to match UIColors

algal

// known-good: Xcode 8.3.3
/*

This shell script outputs which characters are special and need escaping in bash or sh:

#!/bin/bash
special=$'`!@#$%^&*()-_+={}|[]\\;\':",.<>?/ '
for ((i=0; i < ${#special}; i++)); do
    char="${special:i:1}"
    printf -v q_char '%q' "$char"

algal

// known-good: Swift 4, in Xcode Version 9.0 beta 2 (9M137d)
// will be unnecessary once the language can auto-synthesize for this case, or
// when Apple's ships a Codable implementation for CoreGraphics struct types.

extension CGSize : Codable {
  enum CodingKeys: String, CodingKey {
    case width
    case height
  }

algal

// known-good: 8.3.2, Swift 3
/**
Sometimes you just want to launch a synchronous HTTP request for some JSON, damnit.

Other approaches here: https://github.com/algal/SynchronousDownloadPlayground

*/

extension URLSession {
  func sendSynchronousRequest(_ request:URLRequest,

algal

/*

Everyone on Stack Overflow does HTTP Basic Authentication on iOS by manually 
building the HTTP headers.

This amounts to re-implementing HTTP.

Why? The Cocoa Touch URL Loading System aleady knows HTTP, and you can
configure your URLSession to supply HTTP Basic Authentication credentials
like so.

algal

import Foundation

/// Represents side effects needed to sync dst with src
enum Effect {
  /// in dst, remove specified item in dst
  case remove(dstIndex:Int)
  /// in dst, add the specified item from src
  case add(srcIndex:Int)
}

algal

/*
 
 ## background
 
 When you write a function that mutates the var properties of a
 mutable struct, this _creates a new instance_.[1] As a result,
 a variable pointing to a value of this type before the mutation
 will still be pointing to the old value after the mutation, as long
 as you did not use that variable to do the mutation.