11:29 p.m.
For mutable object as a default parameter in function and
method-declarations the problem is, that the evaluation and creation
takes place at exactly the same moment. The python-parser reads the
function-head and evaluates it at the same moment.
Most beginers assume that a new object is created at every call, but
that's not correct. One object (in your example a list) is created at
the moment of declaration and not on demand when you are calling the
method.
For imutable objects that's not a problem, because even if all calls
share the same object, it's imutable and therefore it's properties
remain the same.
As a convention, must be used the None object for defaults to indicate
the use of a default initialization, which now can take place in the
function-body, which naturally is evaluated at call-time.
Signed-off-by: Ramon Medeiros <ramonn(a)linux.vnet.ibm.com>
---
src/wok/exception.py | 4 +++-
src/wok/message.py | 4 +++-
src/wok/model/notifications.py | 4 +++-
3 files changed, 9 insertions(+), 3 deletions(-)
diff --git a/src/wok/exception.py b/src/wok/exception.py
index 52f007e..90b6410 100644
--- a/src/wok/exception.py
+++ b/src/wok/exception.py
@@ -25,7 +25,9 @@ from wok.message import WokMessage
class WokException(Exception):
- def __init__(self, code='', args={}):
+ def __init__(self, code='', args=None):
+ if args is None:
+ args = {}
self.code = code
msg = WokMessage(code, args).get_text()
cherrypy.log.error_log.error(msg)
diff --git a/src/wok/message.py b/src/wok/message.py
index a7162c7..4c35747 100644
--- a/src/wok/message.py
+++ b/src/wok/message.py
@@ -26,7 +26,9 @@ from wok.template import get_lang, validate_language
class WokMessage(object):
- def __init__(self, code='', args={}, plugin=None):
+ def __init__(self, code='', args=None, plugin=None):
+ if args is None:
+ args = {}
# make all args unicode
for key, value in args.iteritems():
if isinstance(value, unicode):
diff --git a/src/wok/model/notifications.py b/src/wok/model/notifications.py
index e83ac56..bdb7c78 100644
--- a/src/wok/model/notifications.py
+++ b/src/wok/model/notifications.py
@@ -27,7 +27,9 @@ from wok.utils import wok_log
notificationsStore = {}
-def add_notification(code, args={}, plugin_name=None):
+def add_notification(code, args=None, plugin_name=None):
+ if args is None:
+ args = {}
if not code:
wok_log.error("Unable to add notification: invalid code
'%(code)s'" %
{'code': str(code)})
--
2.5.5