JSON Decoders talk

• Just get Elm installed with create-elm-app
• Basic Syntax of Elm
• Why JSON decoders?
  • Basically all external services talk in JSON
  • Elm's types are close to JSON but are not the same
  • There's no guerentee that the external thing will return things in the right form. To be safe we have to be defensive
• What is a JSON decoder
  • It's a list of instructions on how to turn JSON into elm types
  • It's a pure data structure not a function, although it can contain functions for the more difficult parts
  • It contains two values:
    • Json to be queried and prodded at
    • A single value of the decoders result so far which can be in one of 3 states:
      • Nothing (you haven't began decoding)
      • A decoded value
      • An Error

talks Elm