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What does new self(); mean in PHP?
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self points to the class in which it is written.
So, if your getInstance method is in a class name MyClass, the following line :
self::$_instance = new self();
Will do the same as :
self::$_instance = new MyClass();
Edit : a couple more informations, after the comments.
If you have two ...
ruby on rails f.select options with custom attributes
I have a form select statement, like this:
5 Answers
5
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android button selector
This is a button selector such that when normal it appears red, when pressed it appears grey.
6 Answers
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Types in MySQL: BigInt(20) vs Int(20)
I was wondering what the difference between BigInt , MediumInt , and Int are... it would seem obvious that they would allow for larger numbers; however, I can make an Int(20) or a BigInt(20) and that would make seem that it is not necessarily about size.
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What is a MIME type?
I have been reading about how to build plug-ins and this "MIME type" keeps getting discussed in it. I have tried to look into it and know that it is Multipurpose Internet Mail Extensions (MIME) but no suitable explanation of how it relates to browser plug-ins, as in what I need to know about it for ...
Python: fastest way to create a list of n lists
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The probably only way which is marginally faster than
d = [[] for x in xrange(n)]
is
from itertools import repeat
d = [[] for i in repeat(None, n)]
It does not have to create a new int object in every iteration and is about 15 % faster on my machine...
Change the name of the :id parameter in Routing resources for Rails
I looked around on how to change the dynamic params slot and found this post that does the exact thing.
The post is https://thoughtbot.com/blog/rails-patch-change-the-name-of-the-id-parameter-in
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Why do we need message brokers like RabbitMQ over a database like PostgreSQL?
I am new to message brokers like RabbitMQ which we can use to create tasks / message queues for a scheduling system like Celery .
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Possible heap pollution via varargs parameter
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Heap pollution is a technical term. It refers to references which have a type that is not a supertype of the object they point to.
List<A> listOfAs = new ArrayList<>();
List<B> listOfBs = (List<B>)(Object)listOfAs; // points to a lis...
Argparse: Required arguments listed under “optional arguments”?
I use the following simple code to parse some arguments; note that one of them is required. Unfortunately, when the user runs the script without providing the argument, the displayed usage/help text does not indicate that there is a non-optional argument, which I find very confusing. How can I get p...