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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.
I...
ruby on rails f.select options with custom attributes
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Rails CAN add custom attributes to select options, using the existing options_for_select helper. You almost had it right in the code in your question. Using html5 data-attributes:
<%= f.select :country_id, options_for_select(
@count...
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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It does not have to create a new int object in every iteration and is about 15 % faster on my machine.
Edit: Using NumPy, you can avoid the Python loop using
d = numpy.empty((n, 0)).tolist()
but this is actually 2.5 times slower than the list comprehension.
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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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When should I use std::thread::detach?
Sometime I have to use std::thread to speed up my application. I also know join() waits until a thread completes. This is easy to understand, but what's the difference between calling detach() and not calling it?
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Possible heap pollution via varargs parameter
I understand this occurs with Java 7 when using varargs with a generic type;
5 Answers
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