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What does “Receiver type 'CALayer' for instance message is a forward declaration” mean here?
I'm porting a block of code from an iOS4 project to iOS5 and I'm having some troubles with ARC. The code generates a PDF from a screen capture.
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The difference between sys.stdout.write and print?
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print is just a thin wrapper that formats the inputs (modifiable, but by default with a space between args and newline at the end) and calls the write function of a given object. By default this object is sys.stdout, but you can pass a file using the "chevron"...
When is std::weak_ptr useful?
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A good example would be a cache.
For recently accessed objects, you want to keep them in memory, so you hold a strong pointer to them. Periodically, you scan the cache and decide which objects have not been accessed recently. You don't need to keep those in m...
Multiple columns index when using the declarative ORM extension of sqlalchemy
According to the documentation and the comments in the sqlalchemy.Column class, we should use the class sqlalchemy.schema.Index to specify an index that contains multiple columns.
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Is it possible to assign numeric value to an enum in Java?
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You cannot use enum constructor in code. EXIT_CODE.A and EXIT_CODE.B are the only instances that will ever exist.
– Bhesh Gurung
Apr 17 '14 at 18:40
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Good way to use table alias in Update statement?
...ng to update rows from within the same table. I want to use a table alias for readability.
2 Answers
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Switch statement fall-through…should it be allowed? [closed]
For as long as I can remember I have avoided using switch statement fall-through. Actually, I can't remember it ever entering my consciousness as a possible way to do things as it was drilled into my head early on that it was nothing more than a bug in the switch statement. However, today I ran acro...
What represents a double in sql server?
I have a couple of properties in C# which are double and I want to store these in a table in SQL Server, but noticed there is no double type, so what is best to use, decimal or float ?
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How do I create a variable number of variables?
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You can use dictionaries to accomplish this. Dictionaries are stores of keys and values.
>>> dct = {'x': 1, 'y': 2, 'z': 3}
>>> dct
{'y': 2, 'x': 1, 'z': 3}
>>> dct["y"]
2
You can use variable key names to achieve the effect of variable variables without the...
How do I check for C++11 support?
Is there a way to detect at compile-time if the compiler supports certain features of C++11? For example, something like this:
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