More protocol 2: TUPLE1, TUPLE2, TUPLE3.
Also moved the special case for empty tuples from save() to save_tuple().
diff --git a/Lib/pickle.py b/Lib/pickle.py
index ca98ae3..aa67ed1 100644
--- a/Lib/pickle.py
+++ b/Lib/pickle.py
@@ -150,6 +150,8 @@
LONG1 = '\x8a' # push long from < 256 bytes
LONG4 = '\x8b' # push really big long
+_tuplesize2code = [EMPTY_TUPLE, TUPLE1, TUPLE2, TUPLE3]
+
__all__.extend([x for x in dir() if re.match("[A-Z][A-Z0-9_]+$",x)])
del x
@@ -257,14 +259,6 @@
t = type(object)
- # XXX Why are tuples a special case here?
- if (t is TupleType) and (len(object) == 0):
- if self.bin:
- self.save_empty_tuple(object)
- else:
- self.save_tuple(object)
- return
-
if d in memo:
self.write(self.get(memo[d][0]))
return
@@ -463,6 +457,24 @@
write = self.write
save = self.save
memo = self.memo
+ proto = self.proto
+
+ if proto >= 1:
+ n = len(object)
+ if n <= 3:
+ if not object:
+ write(EMPTY_TUPLE)
+ return
+ if proto >= 2:
+ for element in object:
+ save(element)
+ # Subtle. Same as in the big comment below
+ if id(object) in memo:
+ get = self.get(memo[id(object)][0])
+ write(POP_MARK + get)
+ else:
+ write(_tuplesize2code[n])
+ return
write(MARK)
for element in object:
@@ -477,15 +489,15 @@
# could have been done in the "for element" loop instead, but
# recursive tuples are a rare thing.
get = self.get(memo[id(object)][0])
- if self.bin:
+ if proto:
write(POP_MARK + get)
else: # proto 0 -- POP_MARK not available
write(POP * (len(object) + 1) + get)
return
- # No recursion (including the empty-tuple case).
+ # No recursion (including the empty-tuple case for protocol 0).
self.write(TUPLE)
- self.memoize(object)
+ self.memoize(object) # XXX shouldn't memoize empty tuple?!
dispatch[TupleType] = save_tuple
@@ -876,6 +888,18 @@
self.stack.append(())
dispatch[EMPTY_TUPLE] = load_empty_tuple
+ def load_tuple1(self):
+ self.stack[-1] = (self.stack[-1],)
+ dispatch[TUPLE1] = load_tuple1
+
+ def load_tuple2(self):
+ self.stack[-2:] = [(self.stack[-2], self.stack[-1])]
+ dispatch[TUPLE2] = load_tuple2
+
+ def load_tuple3(self):
+ self.stack[-3:] = [(self.stack[-3], self.stack[-2], self.stack[-1])]
+ dispatch[TUPLE3] = load_tuple3
+
def load_empty_list(self):
self.stack.append([])
dispatch[EMPTY_LIST] = load_empty_list