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In Django - Model Inheritance - Does it allow you to override a parent model's attribute?
...ld instances (at least,
not at the moment). If a base class has a field called author, you
cannot create another model field called author in any class that
inherits from that base class.
share
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Set select option 'selected', by value
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I had to manually call .val(x).change(); to trigger the select's onChange event, it seems setting val() doesn't fire it.
– scipilot
Jul 19 '15 at 5:48
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Trouble comparing time with RSpec
...olution. I think it's easier and more reliable to just create the date manually:
it "updates updated_at attribute" do
freezed_time = Time.utc(2015, 1, 1, 12, 0, 0) #Put here any time you want
Timecop.freeze(freezed_time) do
patch :update
@article.reload
expect(@article.updated_at).t...
Reset Entity-Framework Migrations
... I used IgnoreChanges on the initial migration, but now I want to delete all my migrations and start with an initial migration with all of the logic.
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Difference between staticmethod and classmethod
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Maybe a bit of example code will help: Notice the difference in the call signatures of foo, class_foo and static_foo:
class A(object):
def foo(self, x):
print "executing foo(%s, %s)" % (self, x)
@classmethod
def class_foo(cls, x):
print "executing class_foo(%s, %s...
Is there an IDictionary implementation that, on missing key, returns the default value instead of th
...
Indeed, that won't be efficient at all.
You could always write an extension method:
public static TValue GetValueOrDefault<TKey,TValue>
(this IDictionary<TKey, TValue> dictionary, TKey key)
{
TValue ret;
// Ignore return value
dic...
How to determine whether a given Linux is 32 bit or 64 bit?
...wk '{print $2}'
Note: you can have a 64-bit CPU with a 32-bit kernel installed.
(as ysdx mentions in his/her own answer, "Nowadays, a system can be multiarch so it does not make sense anyway. You might want to find the default target of the compiler")
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What is the difference between shallow copy, deepcopy and normal assignment operation?
...ble towards the existing object. The docs explain the difference between shallow and deep copies:
The difference between shallow and deep copying is only relevant for
compound objects (objects that contain other objects, like lists or
class instances):
A shallow copy constructs a new...
Is bool a native C type?
... in the current C - C99, but not in C89/90.
In C99 the native type is actually called _Bool, while bool is a standard library macro defined in stdbool.h (which expectedly resolves to _Bool). Objects of type _Bool hold either 0 or 1, while true and false are also macros from stdbool.h.
Note, BTW, t...
This type of CollectionView does not support changes to its SourceCollection from a thread different
...); but it is giving syntax error. Look like Send method is expecting some callback method name. I have tried various options like delegate with parameter but it is not allowing to have my custom parameter. I am very new to this kind of syntax, so it would really helpful if you can provide me synta...