(init params ..body)
  params: an arr
  body: zero or more forms

Defines an initializer method.

To construct an object, invoke its class as though calling a function: (Class a b). This will...

The init clause will automatically prepend field initializers to the beginning of its method body:

Fields are always initialized in the same order that they were declared. This means that field-initializer forms can access fields defined earlier in the same class.

(defclass Example
  (field a)
  (field b (* @a 10))

  (init (@a)
    (prn b)))

; ...is equivalent to...

(defclass Example
  (field a #n)
  (field b #n)

  (init (a)
    (= @a a)
    (= @b (* @a 10))
    (prn b)))