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Correct Bash and shell script variable capitalization
I run across many shell scripts with variables in all caps, and I've always thought that there is a severe misunderstanding with that. My understanding is that, by convention (and perhaps by necessity long ago), environment variables are in all-caps.
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Super-simple example of C# observer/observable with delegates
...
The observer pattern is usually implemented with events.
Here's an example:
using System;
class Observable
{
public event EventHandler SomethingHappened;
public void DoSomething() =>
SomethingHappened?.Invoke(this, EventArgs.Empt...
What is the list of supported languages/locales on Android?
...n_LS [English (Lesotho)]
en_MG [English (Madagascar)]
en_MH [English (Marshall Islands)]
en_MO [English (Macau)]
en_MP [English (Northern Mariana Islands)]
en_MS [English (Montserrat)]
en_MT [English (Malta)]
en_MU [English (Mauritius)]
en_MW [English (Malawi)]
en_NA [English (Namibia)]
en_NF [Engli...
Is generator.next() visible in Python 3?
...son for this is consistency: special methods like __init__() and __del__() all have double underscores (or "dunder" in the current vernacular), and .next() was one of the few exceptions to that rule. This was fixed in Python 3.0. [*]
But instead of calling g.__next__(), use next(g).
[*] There are ...
What is the purpose of python's inner classes?
...dden from the outside world.
More readable, maintainable code: Nesting small classes within top-level classes places the code closer to where it is used.
The main advantage is organization. Anything that can be accomplished with inner classes can be accomplished without them.
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How can I get the current page's full URL on a Windows/IIS server?
I moved a WordPress installation to a new folder on a Windows/ IIS server. I'm setting up 301 redirects in PHP, but it doesn't seem to be working. My post URLs have the following format:
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How to change collation of database, table, column?
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You need to either convert each table individually:
ALTER TABLE mytable CONVERT TO CHARACTER SET utf8mb4
(this will convert the columns just as well), or export the database with latin1 and import it back with utf8mb4.
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Concurrent HashSet in .NET Framework?
...ass.
private ConcurrentBag<string> _data;
Self-implementation
Finally, as you did, you can implement your own data type, using lock or other ways that the .NET provides you to be thread-safe. Here is a great example: How to implement ConcurrentHashSet in .Net
The only drawback of this sol...
How can I force division to be floating point? Division keeps rounding down to 0?
... a floating point number in Python in the following?
c = a / b
What is really being asked here is:
"How do I force true division such that a / b will return a fraction?"
Upgrade to Python 3
In Python 3, to get true division, you simply do a / b.
>>> 1/2
0.5
Floor division, the classic di...
When to use self over $this?
...
$x = new Y();
$x->bar();
?>
The idea is that $this->foo() calls the foo() member function of whatever is the exact type of the current object. If the object is of type X, it thus calls X::foo(). If the object is of type Y, it calls Y::foo(). But with self::foo(), X::foo() is always ...