Exposing 'recur' as a top-level CTCO expression.

Updating the parser to accept the 'recur' form, adding unrecurify to
the list of passes performed by the ctco macro, and correcting a bug
in the implementation of load-tramp for the Recur record.

src/ctco/core.clj

@@ -37,6 +37,7 @@
                 proto/PCpsSrs  (proto/cps-srs expr (gensym "k"))
                 :else (throw (Exception. (str "unexpected expression " expr)))))]
       (let [new-expr (-> (parse/parse expr)
+                         (proto/unrecurify nil)
                          apply-cps
                          proto/thunkify
                          (proto/load-tramp tramp)

src/ctco/expr/recur.clj

@@ -3,7 +3,7 @@
 ;; Written by Chris Frisz
 ;; 
 ;; Created 16 Apr 2012
-;; Last modified 14 Oct 2012
+;; Last modified 19 Oct 2012
 ;; 
 ;; Defines the Recur record type and operations for representing
 ;; 'recur' expressions in the Clojure TCO compiler.
@@ -28,12 +28,15 @@
 ;;----------------------------------------------------------------------
 
 (ns ctco.expr.recur
-  (:require [ctco.protocol :as proto]))
+  (:require [ctco.expr.app]
+            [ctco.protocol :as proto])
+  (:import [ctco.expr.app
+            App]))
 
 (defrecord Recur [arg*]
   proto/PLoadTrampoline
   (load-tramp [this tramp]
-    (proto/walk-expr this f nil))
+    (proto/walk-expr this #(proto/load-tramp % tramp) nil))
 
   proto/PUnparse
   (unparse [this]

src/ctco/parse.clj

@@ -12,13 +12,11 @@
   (:use [clojure.core.match
          :only (match)])
   (:require [ctco.expr
-             app simple def fn if let simple-op]
+             app def fn if let recur simple simple-op]
             [ctco.protocol :as proto]
             [ctco.util :as util])
   (:import [ctco.expr.app
             App]
-           [ctco.expr.simple
-            Simple]
            [ctco.expr.def
             DefSrs DefTriv]
            [ctco.expr.fn
@@ -27,6 +25,10 @@
             IfCps IfSrs IfTriv]
            [ctco.expr.let
             LetCps LetSrs LetTriv]
+           [ctco.expr.recur
+            Recur]
+           [ctco.expr.simple
+            Simple]
            [ctco.expr.simple_op
             SimpleOpCps SimpleOpSrs SimpleOpTriv]))
 
@@ -96,6 +98,11 @@
         (LetSrs. BIND* BODY)
         (LetTriv. BIND* BODY))))
 
+(defn- parse-recur
+  "Helper function for parse that handles 'recur' expressions."
+  [expr*]
+  (Recur. (mapv parse expr*)))
+
 (defn- parse-core
   "Takes a sequence representing a Clojure expression (generally passed from a
   macro) and returns the parsed representation of the expression if it is a core
@@ -111,6 +118,7 @@
     [(['fn (name :guard symbol?) & body*] :seq)] (parse-fn name body*)
     [(['if test conseq alt] :seq)] (parse-if test conseq alt)
     [(['let bind* body] :seq)] (parse-let bind* body)
+    [(['recur & expr*] :seq)] (parse-recur expr*)
     :else false))
 
 (defn- parse-defn