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how can you easily check if access is denied for a file in .NET?
...e to check if I have rights to open the file before I actually try to open it; I do not want to use a try/catch for this check unless I have to. Is there a file access property I can check before hand?
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What is the fastest way to compute sin and cos together?
...ns simultaneously. If you need strong optimization, perhaps you should use it.
Here is a small example: http://home.broadpark.no/~alein/fsincos.html
Here is another example (for MSVC): http://www.codeguru.com/forum/showthread.php?t=328669
Here is yet another example (with gcc): http://www.allegro...
How to create GUID / UUID?
... are identifiers designed to provide certain uniqueness guarantees.
While it is possible to implement an RFC-compliant UUIDs in a few lines of JS (E.g. see @broofa's answer, below) there are several common pitfalls:
Invalid id format (UUIDs must be of the form "xxxxxxxx-xxxx-Mxxx-Nxxx-xxxxxxxxxxx...
How to determine whether a given Linux is 32 bit or 64 bit?
When I type uname -a , it gives the following output.
21 Answers
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When is “i += x” different from “i = i + x” in Python?
...This depends entirely on the object i.
+= calls the __iadd__ method (if it exists -- falling back on __add__ if it doesn't exist) whereas + calls the __add__ method1 or the __radd__ method in a few cases2.
From an API perspective, __iadd__ is supposed to be used for modifying mutable objects i...
Interfaces with static fields in java for sharing 'constants'
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It's generally considered bad practice. The problem is that the constants are part of the public "interface" (for want of a better word) of the implementing class. This means that the implementing class is publishing all of...
Why don't structs support inheritance?
I know that structs in .NET do not support inheritance, but its not exactly clear why they are limited in this way.
10 An...
What does Serializable mean?
What exactly does it mean for a class to be Serializable in Java? Or in general, for that matter...
10 Answers
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Performance of Arrays vs. Lists
Say you need to have a list/array of integers which you need iterate frequently, and I mean extremely often. The reasons may vary, but say it's in the heart of the inner most loop of a high volume processing.
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Where do “pure virtual function call” crashes come from?
I sometimes notice programs that crash on my computer with the error: "pure virtual function call".
8 Answers
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