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C# difference between == and Equals()
...resolve to System.Object.ReferenceEquals.
Equals is just a virtual method and behaves as such, so the overridden version will be used (which, for string type compares the contents).
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Why aren't superclass __init__ methods automatically invoked?
...methods of their superclasses, as in some other languages? Is the Pythonic and recommended idiom really like the following?
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What it the significance of the Javascript constructor property?
Trying to bend by head around Javascript's take on OO...and, like many others, running into confusion about the constructor property. In particular, the significance of the constructor property, as I can't seem to make it have any effect. E.g.:
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Thou shalt not inherit from std::vector
... the hell it is before using it. What's the difference between std::vector and MyVector? Which one is better to use here and there? What if I need to move std::vector to MyVector? May I just use swap() or not?
Do not produce new entities just to make something to look better. These entities (especi...
What is the difference between a var and val definition in Scala?
What is the difference between a var and val definition in Scala and why does the language need both? Why would you choose a val over a var and vice versa?
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How to output only captured groups with sed?
...as well as specifying what you do want.
string='This is a sample 123 text and some 987 numbers'
echo "$string" | sed -rn 's/[^[:digit:]]*([[:digit:]]+)[^[:digit:]]+([[:digit:]]+)[^[:digit:]]*/\1 \2/p'
This says:
don't default to printing each line (-n)
exclude zero or more non-digits
include on...
When to use PNG or JPG in iPhone development?
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PNG's are pixel perfect (non-lossy), and require very little extra CPU energy to display. However, large PNGs may take longer to read from storage than more compressed image formats, and thus be slower to display.
JPG's are smaller to store, but lossy (amount ...
Android ViewPager - Show preview of page on left and right
I'm using Android's ViewPager . What I want to do is to show a preview of the page on both the left and the right. I've seen where I can use a negative pageMargin to show a preview of the right side.
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Git mergetool with Meld on Windows
In Linux, my favorite merge tool is Meld, and I've had no problems using or configuring it to work with Git. However, in Windows it has been a different story.
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How to exit an if clause
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(This method works for ifs, multiple nested loops and other constructs that you can't break from easily.)
Wrap the code in its own function. Instead of break, use return.
Example:
def some_function():
if condition_a:
# do something and return early
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