gistfile1.clj

(ns clojure.core)

(declare cons)

(defprotocol ISeq
  (first [coll])
  (rest [coll])
  (next [coll]))

(defprotocol Seqable
  (seq [coll]))

(defprotocol IPersistentCollection
  (conj [coll val]))

(defprotocol IMeta
  (meta [obj])
  (with-meta [obj meta]))

(defprotocol Show
  (show [obj]))

(deftype Cons [_first _rest _meta]
  IPersistentCollection
  (conj [coll val] (Cons. val coll))

  ISeq
  (first [coll] _first)
  (rest [coll] (or _rest ()))
  (next [coll] (or _rest nil))

  Seqable
  (seq [coll] (cons _first _rest))

  IMeta
  (meta [obj] _meta)
  (with-meta [obj meta] (Cons. _first _rest meta))

  Show
  (show [obj] (eval `(str "(" ~_first ~@_rest ")"))))

(defn cons
  [x xs]
  (Cons. x xs))

(deftype Symbol [_ns _name _meta]
  IMeta
  (meta [obj] _meta)
  (with-meta [obj meta] (Symbol. _ns _name meta))

  Show
  (show [sym]
    (if _ns
      (str _ns "/" _name)
      (str _name))))

(deftype Keyword [_ns _name]
  Show
  (show [kw]
    (if _ns
      (str ":" _ns "/" _name)
      (str ":" _name))))

(deftype Char [ch]  
  Show
  (show [c] (str \\ ch)))

(deftype String [chars]  
  Show
  (show [s] (str \" chars \")))

(defn str
  ([] "")
  ([x] (show x))
  ([x & ys]))

(defprotocol Num
  (+ [] [x] [x y] [x y & more])
  (- [] [x] [x y] [x y & more])
  (* [] [x] [x y] [x y & more])
  (/ [] [x] [x y] [x y & more]))

(defprotocol Real
  (rationalize [num]))

(defprotocol Integral
  (quot [num div])
  (rem [num div])
  (mod [num div])
  (int [x]))

(deftype BigInt []
  Num
  (+ [] [x] [x y] [x y & more])
  (- [] [x] [x y] [x y & more])
  (* [] [x] [x y] [x y & more])
  (/ [] [x] [x y] [x y & more]))

(deftype Ratio [numerator denominator]
  Num
  (+ [] [x] [x y] [x y & more])
  (- [] [x] [x y] [x y & more])
  (* [] [x] [x y] [x y & more])
  (/ [] [x] [x y] [x y & more]))