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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:
...
How are the points in CSS specificity calculated
...
Pekka's answer is practically correct, and probably the best way to think about the issue.
However, as many have already pointed out, the W3C CSS recommendation states that "Concatenating the three numbers a-b-c (in a number system with a large base) gives the sp...
CSS Pseudo-classes with inline styles
...g the delimiting braces), whose formal grammar is given below in the terms and conventions of the CSS core grammar:
declaration-list
: S* declaration? [ ';' S* declaration? ]*
;
Neither selectors (including pseudo-elements), nor at-rules, nor any other CSS construct are allowed.
Think of inlin...
Why have header files and .cpp files? [closed]
Why does C++ have header files and .cpp files?
9 Answers
9
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Fastest method of screen capturing on Windows
...to use GDI, but I'm curious whether there are other ways to go about this, and, if there are, which incurs the least overhead? Speed is a priority.
...
MySQL SELECT WHERE datetime matches day (and not necessarily time)
...rds, if my table only contained the following 4 records, then only the 2nd and 3rd would be returned if I limit to 2012-12-25.
...
NameError: global name 'xrange' is not defined in Python 3
...ror but a runtime exception instead.
If you do know what your are doing and are actively making a Python 2 codebase compatible with Python 3, you can bridge the code by adding the global name to your module as an alias for range. (Take into account that you may have to update any existing range()...
How to include a child object's child object in Entity Framework 5
I am using Entity Framework 5 code first and ASP.NET MVC 3 .
4 Answers
4
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MySQL DISTINCT on a GROUP_CONCAT()
...n a string like:
test1 test2 test3 test1 test3 test4
(notice that test1 and test3 are duplicated) while the OP wants to return this string:
test1 test2 test3 test4
the problem here is that the string "test1 test3" is duplicated and is inserted only once, but all of the others are distinct to e...
Get time difference between two dates in seconds
...he explanation
You need to call the getTime() method for the Date objects, and then simply subtract them and divide by 1000 (since it's originally in milliseconds). As an extra, when you're calling the getDate() method, you're in fact getting the day of the month as an integer between 1 and 31 (not ...