Declaring Records: The Art of Structured Procrastination

Record declarations in LFE use the defrecord form, which looks refreshingly similar to how you’d explain the concept to a particularly bright parrot:

(defrecord person
  name
  (age 0)           ; default value
  (phone ""))       ; another default

This declares a record type called person with three fields. The age field defaults to 0 (presumably for immortal beings or those who refuse to acknowledge the passage of time), and phone defaults to an empty string (for those ahead-of-their-time individuals who hadn’t invented the telephone yet).

You can also write this in the more explicit form, should you feel the need to be unnecessarily verbose:

(defrecord person
  (name 'undefined)
  (age 0)
  (phone ""))

The atom 'undefined is Erlang’s way of saying “I have no idea what goes here, but I’m sure it’ll come to me eventually.”