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Reliable method to get machine's MAC address in C#
...work across OS. Any ideas? I have been scraping the output of "ipconfig /all" but this is terribly unreliable as the output format differs on every machine.
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Does ARC support dispatch queues?
...d as
* Objective-C types when building with an Objective-C compiler. This allows
* them to participate in ARC, in RR management by the Blocks runtime and in
* leaks checking by the static analyzer, and enables them to be added to Cocoa
* collections.
*
* NOTE: this requires explicit cancellati...
An async/await example that causes a deadlock
...lick for UI / MyController.Get for ASP.NET):
The top-level method calls GetJsonAsync (within the UI/ASP.NET context).
GetJsonAsync starts the REST request by calling HttpClient.GetStringAsync (still within the context).
GetStringAsync returns an uncompleted Task, indicating the REST requ...
Efficient way to determine number of digits in an integer
...For added efficiency, if you know that your input numbers will be mostly small ones (I'm guessing less than 100,000), then reverse the tests: if (x < 10) return 1; if (x < 100) return 2; etc., so that the function will do less tests and exit faster.
– squelart
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Purpose of Python's __repr__
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__repr__ should return a printable representation of the object, most likely one of the ways possible to create this object. See official documentation here. __repr__ is more for developers while __str__ is for end users.
A ...
“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
... can be used to detect if a variable has been already initialized. Additionally and more ideal is the solution of empty() since it does not generate a warning or error message if the variable is not initialized.
From PHP documentation:
No warning is generated if the variable does not exist. T...
Can't start Eclipse - Java was started but returned exit code=13
...ng Eclipse. I ran into this problem when trying to run Eclipse, having installed version 4.2 only minutes ago.
44 Answers
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How to compare times in Python?
...use for comparison without taking the date into account:
>>> this_morning = datetime.datetime(2009, 12, 2, 9, 30)
>>> last_night = datetime.datetime(2009, 12, 1, 20, 0)
>>> this_morning.time() < last_night.time()
True
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Relative imports in Python 2.7
... not determine what package Python thinks it is in. That depends, additionally, on how you load the file into Python (by running or by importing).
There are two ways to load a Python file: as the top-level script, or as a
module. A file is loaded as the top-level script if you execute it directl...
C# Lazy Loaded Automatic Properties
... 4.0 Lazy<T> type to create this pattern
private Lazy<string> _someVariable =new Lazy<string>(SomeClass.IOnlyWantToCallYouOnce);
public string SomeVariable => _someVariable.Value;
This code will lazily calculate the value of _someVariable the first time the Value expression i...