OliverJAsh

Tagged unions are a way of saying "this data is any one of these values", and the tag is a property that discriminates the values. It enables some really powerful type system features, like exhaustive checking and control flow analysis.

Tagged unions also go by the name of: tagged unions, discriminated unions, algebraic data types (ADTs), and sum types. Just to confuse matters.

In many functional languages this is a really common pattern, like Haskell, Elm, PureScript, and Scala. So much so, they have their own native syntax.

For example, in Elm we can define a tagged union representing an anonymous or named user with:

// elm

paf31

This blog post series has moved here.

You might also be interested in the 2016 version.

ryboe

OBSOLETE PREFIXES
    -xv-interpret-as      // -xv- and -o- are old Opera prefixes for the Presto
    -xv-phonemes          // engine. Opera switched to the Blink engine with
    -xv-voice-balance     // version 15. The current version is 34.
    -xv-voice-duration
    -xv-voice-pitch
    -xv-voice-pitch-range
    -xv-voice-rate
    -xv-voice-stress
    -xv-voice-volume

mxswd

// this is a playground
protocol Nat {
  class func construct() -> Self
  class func value() -> Int
}

struct Z : Nat {
  static func construct() -> Z {
    return Z()
  }

staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

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This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

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