Remove the lfu_cache. Add more tests.

1 files changed, 15 insertions, 28 deletions

diff --git a/Doc/whatsnew/3.2.rst b/Doc/whatsnew/3.2.rst
index bc31764..2c625a8 100644
--- a/Doc/whatsnew/3.2.rst
+++ b/Doc/whatsnew/3.2.rst
@@ -66,45 +66,32 @@ Some smaller changes made to the core Python language are:
 New, Improved, and Deprecated Modules
 =====================================
 
-* The functools module now includes two new decorators for caching function
-  calls, :func:`functools.lru_cache` and :func:`functools.lfu_cache`. These can
-  save repeated queries to an external resource whenever the results are
-  expected to be the same.
+* The functools module now includes a new decorator for caching function calls.
+  :func:`functools.lru_cache` can save repeated queries to an external resource
+  whenever the results are expected to be the same.
 
   For example, adding a caching decorator to a database query function can save
   database accesses for popular searches::
 
-      @functools.lfu_cache(maxsize=50)
+      @functools.lru_cache(maxsize=300)
       def get_phone_number(name):
           c = conn.cursor()
           c.execute('SELECT phonenumber FROM phonelist WHERE name=?', (name,))
           return c.fetchone()[0]
 
-  The caches support two strategies for limiting their size to *maxsize*. The
-  LFU (least-frequently-used) cache works bests when popular queries remain the
-  same over time.  In contrast, the LRU (least-recently-used) cache works best
-  query popularity changes over time (for example, the most popular news
-  articles change each day as newer articles are added).
-
-  The two caching decorators can be composed (nested) to handle hybrid cases.
-  For example, music searches can reflect both long-term patterns (popular
-  classics) and short-term trends (new releases)::
-
-        @functools.lfu_cache(maxsize=500)
-        @functools.lru_cache(maxsize=100)
-        def find_lyrics(song):
-            query = 'http://www.example.com/songlist/%s' % urllib.quote(song)
-            page = urllib.urlopen(query).read()
-            return parse_lyrics(page)
-
-  To help with choosing an effective cache size, the wrapped function
-  is instrumented with two attributes *hits* and *misses*::
-
-        >>> for song in user_requests:
-        ...     find_lyrics(song)
-        >>> print(find_lyrics.hits, find_lyrics.misses)
+  To help with choosing an effective cache size, the wrapped function is
+  instrumented with two attributes *hits* and *misses*::
+
+        >>> for name in user_requests:
+        ...     get_phone_number(name)
+        >>> print(get_phone_number.hits, get_phone_number.misses)
         4805 980
 
+  If the phonelist table gets updated, the outdated contents of the cache can be
+  cleared with::
+
+        >>> get_phone_number.clear()
+
   (Contributed by Raymond Hettinger)
 
 * The previously deprecated :func:`contextlib.nested` function has been