[Python-modules-commits] r7028 - in packages (5 files)

[morph at users.alioth.debian.org]

    Date: Saturday, November 29, 2008 @ 21:47:31
  Author: morph
Revision: 7028

[svn-inject] Installing original source of logilab-common

Added:
  packages/logilab-common/
  packages/logilab-common/branches/
  packages/logilab-common/branches/upstream/
  packages/logilab-common/branches/upstream/current/
  packages/logilab-common/branches/upstream/current/decorators.py

Added: packages/logilab-common/branches/upstream/current/decorators.py
===================================================================
--- packages/logilab-common/branches/upstream/current/decorators.py	                        (rev 0)
+++ packages/logilab-common/branches/upstream/current/decorators.py	2008-11-29 21:47:31 UTC (rev 7028)
@@ -0,0 +1,124 @@
+# This program is free software; you can redistribute it and/or modify it under
+# the terms of the GNU General Public License as published by the Free Software
+# Foundation; either version 2 of the License, or (at your option) any later
+# version.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# this program; if not, write to the Free Software Foundation, Inc.,
+# 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+"""this module contains some function/method decorators
+
+:author:    Logilab
+:copyright: 2006-2008 LOGILAB S.A. (Paris, FRANCE)
+:contact:   http://www.logilab.fr/ -- mailto:python-projects at logilab.org
+"""
+__docformat__ = "restructuredtext en"
+
+# XXX rewrite so we can use the decorator syntax when keyarg has to be specified
+
+def cached(callableobj, keyarg=None):
+    """simple decorator to cache result of method call"""
+    #print callableobj, keyarg, callableobj.func_code.co_argcount
+    if callableobj.func_code.co_argcount == 1 or keyarg == 0:
+        
+        def cache_wrapper1(self, *args):
+            cache = '_%s_cache_' % callableobj.__name__
+            #print 'cache1?', cache
+            try:
+                return self.__dict__[cache]
+            except KeyError:
+                #print 'miss'
+                value = callableobj(self, *args)
+                setattr(self, cache, value)
+                return value
+        return cache_wrapper1
+    
+    elif keyarg:
+        
+        def cache_wrapper2(self, *args, **kwargs):
+            cache = '_%s_cache_' % callableobj.__name__
+            key = args[keyarg-1]
+            #print 'cache2?', cache, self, key
+            try:
+                _cache = self.__dict__[cache]
+            except KeyError:
+                #print 'init'
+                _cache = {}
+                setattr(self, cache, _cache)
+            try:
+                return _cache[key]
+            except KeyError:
+                #print 'miss', self, cache, key
+                _cache[key] = callableobj(self, *args, **kwargs)
+            return _cache[key]
+        return cache_wrapper2
+
+    def cache_wrapper3(self, *args):
+        cache = '_%s_cache_' % callableobj.__name__
+        #print 'cache3?', cache, self, args
+        try:
+            _cache = self.__dict__[cache]
+        except KeyError:
+            #print 'init'
+            _cache = {}
+            setattr(self, cache, _cache)
+        try:
+            return _cache[args]
+        except KeyError:
+            #print 'miss'
+            _cache[args] = callableobj(self, *args)
+        return _cache[args]
+    return cache_wrapper3
+
+def clear_cache(obj, funcname):
+    """function to clear a cache handled by the cached decorator"""
+    try:
+        del obj.__dict__['_%s_cache_' % funcname]
+    except KeyError:
+        pass
+
+def copy_cache(obj, funcname, cacheobj):
+    """copy cache for <funcname> from cacheobj to obj"""
+    cache = '_%s_cache_' % funcname
+    try:
+        setattr(obj, cache, cacheobj.__dict__[cache])
+    except KeyError:
+        pass
+
+
+class wproperty(object):
+    """simple descriptor expecting to take a modifier function as first argument
+    and looking for a _<function name> to retreive the attribute
+    """
+    def __init__(self, setfunc):
+        self.setfunc = setfunc
+        self.attrname = '_%s' % setfunc.__name__
+        
+    def __set__(self, obj, value):
+        self.setfunc(obj, value)
+        
+    def __get__(self, obj, cls):
+        assert obj is not None
+        return getattr(obj, self.attrname)
+
+
+class classproperty(object):
+    def __init__(self, get):
+        self.get = get
+    def __get__(self, inst, cls):
+        return self.get(cls)
+
+from time import clock
+def timed(f):
+    def wrap(*args, **kwargs):
+        t = clock()
+        #for i in range(100):
+        res = f(*args, **kwargs)
+        print '%s time: %.9f' % (f.__name__, clock() - t)
+        return res
+    return wrap
+