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Is there a practical use for weak references? [duplicate]
Since weak references can be claimed by the garbage collector at any time, is there any practical reason for using them?
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Calling Objective-C method from C++ member function?
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Hi, I tried it but I get linkage error saying symbol(s) not found. i.e. it can't find the MyObjectDoSomethingWith. any ideas?
– user83950
Jan 18 '10 at 7:23
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Undo git reset --hard with uncommitted files in the staging area
...it. But I knew the commit hash, so I was able to do git cherry-pick COMMIT_HASH to restore it.
I did this within a few minutes of losing the commit, so it may work for some of you.
share
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Cannot create an NSPersistentStoreCoordinator with a nil model
Been having my first crack at Core Data and I'm getting the following error when running my code on my device, but it works fine on the simulator..
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What are the “standard unambiguous date” formats for string-to-date conversion in R?
...' then '"%Y/%m/%d"' on the first non-'NA' element,
and give an error if neither works.
as.Date("01 Jan 2000") yields an error because the format isn't one of the two listed above. as.Date("01/01/2000") yields an incorrect answer because the date isn't in one of the two formats listed...
import module from string variable
...om a string, and get the same behavior as just import. And try/except the error case, too. :)
pipmodules = ['pycurl', 'ansible', 'bad_module_no_beer']
for module in pipmodules:
try:
# because we want to import using a variable, do it this way
module_obj = __import__(m...
How can I filter a date of a DateTimeField in Django?
...ised it got 4 upvotes, because when I try the contains solution, I get the error message: Unable to get repr for <class 'django.db.models.query.QuerySet'>
– Houman
Jan 13 '13 at 13:13
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Why does @foo.setter in Python not work for me?
...t;
File "/devel/class_test.py", line 6, in x
return self._x
AttributeError: 'testDec' object has no attribute '_x'
>>> k.x = 5
called setter
>>> k.x
called getter
5
>>>
Another detail that might cause problems is that both methods need the same name for the proper...
Why are arrays covariant but generics are invariant?
...t[] objects = strings; // valid, String[] is Object[]
objects[0] = 12; // error, would cause java.lang.ArrayStoreException: java.lang.Integer during runtime
If this was allowed with generic collections:
List<String> strings = new ArrayList<String>();
List<Object> objects = stri...