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Should I instantiate instance variables on declaration or in the constructor?
...he compiler.
The first variant is more readable.
You can't have exception handling with the first variant.
There is additionally the initialization block, which is as well put in the constructor(s) by the compiler:
{
a = new A();
}
Check Sun's explanation and advice
From this tutorial:
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Why does PHP 5.2+ disallow abstract static class methods?
After enabling strict warnings in PHP 5.2, I saw a load of strict standards warnings from a project that was originally written without strict warnings:
...
What is the MySQL VARCHAR max size?
...ySQL table has a maximum row size limit of 65,535 bytes, not counting BLOB and TEXT types. BLOB and TEXT columns only contribute 9 to 12 bytes toward the row size limit because their contents are stored separately from the rest of the row. Read more about Limits on Table Column Count and Row Size.
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JPG vs. JPEG image formats
I often use JPEG images, and I have noticed that there are two very similar file extensions: .jpg , which my mobile's camera and the Preview application use, and .jpeg , with which Image Capture saves the images from scanning with my Canon MX455 printer. LaTeX doesn't seem to distinguish...
Is there any kind of hash code function in JavaScript?
...d, alternatively, maintain an array which indexes the objects in question, and use its index string as a reference to the object. Something like this:
var ObjectReference = [];
ObjectReference.push(obj);
set['ObjectReference.' + ObjectReference.indexOf(obj)] = true;
Obviously it's a little verbo...
What is Inversion of Control?
...
The Inversion of Control (IoC) and Dependency Injection (DI) patterns are all about removing dependencies from your code.
For example, say your application has a text editor component and you want to provide spell checking. Your standard code would look so...
UIActivityViewController crashing on iOS 8 iPads
... Xcode 6 (Beta 6). UIActivityViewController works fine with iPhone devices and simulators but crashes with iPad simulators and devices (iOS 8) with following logs
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CSS Selector “(A or B) and C”?
...(.a .b) .c {
/* stuff goes here */
}
You can find more info on it here and here. Currently, most browsers support its initial version :any(), which works the same way, but will be replaced by :matches(). We just have to wait a little more before using this everywhere (I surely will).
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Entity Framework and Connection Pooling
...ecently started to use the Entity Framework 4.0 in my .NET 4.0 application and am curious about a few things relating to pooling.
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How can I make a TextArea 100% width without overflowing when padding is present in CSS?
I have the following CSS and HTML snippet being rendered.
15 Answers
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