From 77dd732a3b3b604a6029e748ffd4fb0b9760642d Mon Sep 17 00:00:00 2001
From: Fredrik Tolf <fredrik@dolda2000.com>
Date: Sat, 2 Feb 2013 06:25:37 +0100
Subject: [PATCH] Moved the iterproxy to an optionally usable preiter in
 wrw.util.

---
 wrw/dispatch.py | 28 +---------------------------
 wrw/util.py     | 31 +++++++++++++++++++++++++++++++
 2 files changed, 32 insertions(+), 27 deletions(-)

diff --git a/wrw/dispatch.py b/wrw/dispatch.py
index fa1f669..4d22b72 100644
--- a/wrw/dispatch.py
+++ b/wrw/dispatch.py
@@ -16,32 +16,6 @@ def mangle(result):
         return result
     return [str(result)]
 
-class iterproxy(object):
-    # Makes sure iter(real).next() is called immediately, in order to
-    # let generator code run.
-    def __init__(self, real):
-        self.bk = real
-        self.bki = iter(real)
-        self._next = [None]
-        self.next()
-
-    def __iter__(self):
-        return self
-
-    def next(self):
-        if self._next is None:
-            raise StopIteration()
-        ret = self._next[0]
-        try:
-            self._next[:] = [self.bki.next()]
-        except StopIteration:
-            self._next = None
-        return ret
-
-    def close(self):
-        if hasattr(self.bk, "close"):
-            self.bk.close()
-
 def defaulterror(req, excinfo):
     import resp
     traceback.print_exception(*excinfo)
@@ -60,7 +34,7 @@ def handle(req, startreq, handler):
         resp = [""]
         while True:
             try:
-                resp = iterproxy(handler(req))
+                resp = handler(req)
                 break
             except restart, i:
                 handler = i.handle
diff --git a/wrw/util.py b/wrw/util.py
index 6368b18..55b4ee2 100644
--- a/wrw/util.py
+++ b/wrw/util.py
@@ -34,6 +34,37 @@ def persession(data = None):
         return wrapper
     return dec
 
+class preiter(object):
+    __slots__ = ["bk", "bki", "_next"]
+    end = object()
+    def __init__(self, real):
+        self.bk = real
+        self.bki = iter(real)
+        self._next = None
+        self.next()
+
+    def __iter__(self):
+        return self
+
+    def next(self):
+        if self._next is self.end:
+            raise StopIteration()
+        ret = self._next
+        try:
+            self._next = next(self.bki)
+        except StopIteration:
+            self._next = self.end
+        return ret
+
+    def close(self):
+        if hasattr(self.bk, "close"):
+            self.bk.close()
+
+def pregen(callable):
+    def wrapper(*args, **kwargs):
+        return preiter(callable(*args, **kwargs))
+    return wrapper
+
 class sessiondata(object):
     @classmethod
     def get(cls, req, create = True):
-- 
2.11.0