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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...
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...
findViewByID returns null
... I read all the other threads on this topic. And not only those from this site... (you see, I'm a little frustrated)
29 Ans...
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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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...
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 is the tilde (~) in the enum definition?
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~ is the unary one's complement operator -- it flips the bits of its operand.
~0 = 0xFFFFFFFF = -1
in two's complement arithmetic, ~x == -x-1
the ~ operator can be found in pretty much any language that borrowed syntax from C, including Objective-C/C++/C#/Java/Java...
'Static readonly' vs. 'const'
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public static readonly fields are a little unusual; public static properties (with only a get) would be more common (perhaps backed by a private static readonly field).
const values are burned directly into the call-site; this is double edged:
it is useless i...
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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