def _printLn(s string) MalVal {
  printLn(s)
  return gNil
}

const ns StringMap<fn(List<MalVal>) MalVal> = {
  "eval":  (a List<MalVal>) => EVAL(a[0], repl_env),
  "=":     (a List<MalVal>) => MalVal.fromBool(a[0].equal(a[1])),
  "throw": (a List<MalVal>) => { throw MalUserError.new(a[0]) },

  "nil?":     (a List<MalVal>) => MalVal.fromBool(a[0] is MalNil),
  "true?":    (a List<MalVal>) => MalVal.fromBool(a[0] is MalTrue),
  "false?":   (a List<MalVal>) => MalVal.fromBool(a[0] is MalFalse),
  "string?":  (a List<MalVal>) => MalVal.fromBool(a[0] is MalString),
  "symbol":   (a List<MalVal>) => MalSymbol.new((a[0] as MalString).val),
  "symbol?":  (a List<MalVal>) => MalVal.fromBool(a[0] is MalSymbol),
  "keyword":  (a List<MalVal>) => MalKeyword.new((a[0] as MalString).val),
  "keyword?": (a List<MalVal>) => MalVal.fromBool(a[0] is MalKeyword),
  "number?":  (a List<MalVal>) => MalVal.fromBool(a[0] is MalNumber),
  "fn?":      (a List<MalVal>) => MalVal.fromBool(a[0] is MalNativeFunc ||
                                                  (a[0] is MalFunc && !(a[0] as MalFunc).isMacro)),
  "macro?":   (a List<MalVal>) => MalVal.fromBool(a[0] is MalFunc && (a[0] as MalFunc).isMacro),

  "pr-str":  (a List<MalVal>) => MalString.new(" ".join(a.map<string>(e => pr_str(e, true)))),
  "str":     (a List<MalVal>) => MalString.new("".join(a.map<string>(e => pr_str(e, false)))),
  "prn":     (a List<MalVal>) => _printLn(" ".join(a.map<string>(e => pr_str(e, true)))),
  "println": (a List<MalVal>) => _printLn(" ".join(a.map<string>(e => pr_str(e, false)))),
  "read-string": (a List<MalVal>) => read_str((a[0] as MalString).val),
  "readline":    (a List<MalVal>) => {
                   const line = readLine((a[0] as MalString).val)
                   return line == null ? gNil : MalString.new(line)
                 },
  "slurp":   (a List<MalVal>) => MalString.new(readFile((a[0] as MalString).val)),

  "<":  (a List<MalVal>) => MalVal.fromBool((a[0] as MalNumber).val < (a[1] as MalNumber).val),
  "<=": (a List<MalVal>) => MalVal.fromBool((a[0] as MalNumber).val <= (a[1] as MalNumber).val),
  ">":  (a List<MalVal>) => MalVal.fromBool((a[0] as MalNumber).val > (a[1] as MalNumber).val),
  ">=": (a List<MalVal>) => MalVal.fromBool((a[0] as MalNumber).val >= (a[1] as MalNumber).val),
  "+":  (a List<MalVal>) => MalNumber.new((a[0] as MalNumber).val + (a[1] as MalNumber).val),
  "-":  (a List<MalVal>) => MalNumber.new((a[0] as MalNumber).val - (a[1] as MalNumber).val),
  "*":  (a List<MalVal>) => MalNumber.new((a[0] as MalNumber).val * (a[1] as MalNumber).val),
  "/":  (a List<MalVal>) => MalNumber.new((a[0] as MalNumber).val / (a[1] as MalNumber).val),
  "time-ms": (a List<MalVal>) => MalNumber.new(timeMs),

  "list":      (a List<MalVal>) => MalList.new(a),
  "list?":     (a List<MalVal>) => MalVal.fromBool(a[0] is MalList),
  "vector":    (a List<MalVal>) => MalVector.new(a),
  "vector?":   (a List<MalVal>) => MalVal.fromBool(a[0] is MalVector),
  "hash-map":  (a List<MalVal>) => MalHashMap.fromList(a),
  "map?":      (a List<MalVal>) => MalVal.fromBool(a[0] is MalHashMap),
  "assoc":     (a List<MalVal>) => (a[0] as MalHashMap).assoc(a.slice(1)),
  "dissoc":    (a List<MalVal>) => (a[0] as MalHashMap).dissoc(a.slice(1)),
  "get":       (a List<MalVal>) => a[0] is MalNil ? gNil : (a[0] as MalHashMap).get(a[1]),
  "contains?": (a List<MalVal>) => MalVal.fromBool((a[0] as MalHashMap).contains(a[1])),
  "keys":      (a List<MalVal>) => MalList.new((a[0] as MalHashMap).keys),
  "vals":      (a List<MalVal>) => MalList.new((a[0] as MalHashMap).vals),

  "sequential?": (a List<MalVal>) => MalVal.fromBool(a[0] is MalSequential),
  "cons":   (a List<MalVal>) => {
              var list List<MalVal> = (a[1] as MalSequential).val.clone
              list.prepend(a[0])
              return MalList.new(list)
            },
  "concat": (a List<MalVal>) => {
              var list List<MalVal> = []
              a.each(e => list.append((e as MalSequential).val))
              return MalList.new(list)
            },
  "nth":    (a List<MalVal>) => (a[0] as MalSequential).nth((a[1] as MalNumber).val),
  "first":  (a List<MalVal>) => a[0] is MalNil ? gNil : (a[0] as MalSequential).first,
  "rest":   (a List<MalVal>) => a[0] is MalNil ? MalList.new([]) : (a[0] as MalSequential).rest,
  "empty?": (a List<MalVal>) => MalVal.fromBool((a[0] as MalSequential).count == 0),
  "count":  (a List<MalVal>) => a[0] is MalNil ? MalNumber.new(0) : MalNumber.new((a[0] as MalSequential).count),
  "apply":  (a List<MalVal>) => {
              const f = a[0] as MalCallable
              var args = a.slice(1, a.count - 1)
              args.append((a[a.count - 1] as MalSequential).val)
	      return f.call(args)
            },
  "map":    (a List<MalVal>) => {
              const f = a[0] as MalCallable
              return MalList.new((a[1] as MalSequential).val.map<MalVal>(e => f.call([e])))
            },

  "conj": (a List<MalVal>) => (a[0] as MalSequential).conj(a.slice(1)),
  "seq":  (a List<MalVal>) => a[0].seq,

  "meta":      (a List<MalVal>) => a[0].meta,
  "with-meta": (a List<MalVal>) => a[0].withMeta(a[1]),
  "atom":      (a List<MalVal>) => MalAtom.new(a[0]),
  "atom?":     (a List<MalVal>) => MalVal.fromBool(a[0] is MalAtom),
  "deref":     (a List<MalVal>) => (a[0] as MalAtom).val,
  "reset!":    (a List<MalVal>) => (a[0] as MalAtom).resetBang(a[1]),
  "swap!":     (a List<MalVal>) => {
                 var atom = a[0] as MalAtom
                 const oldVal = atom.val
                 var callArgs = a.slice(2)
                 callArgs.prepend(oldVal)
                 const newVal = (a[1] as MalCallable).call(callArgs)
                 return atom.resetBang(newVal)
               },
}