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What does default(object); do in C#?
... worth making it explicit)
The biggest use of default(T) is in generics, and things like the Try... pattern:
bool TryGetValue(out T value) {
if(NoDataIsAvailable) {
value = default(T); // because I have to set it to *something*
return false;
}
value = GetData();
re...
Loop code for each file in a directory [duplicate]
I have a directory of pictures that I want to loop through and do some file calculations on. It might just be lack of sleep, but how would I use PHP to look in a given directory, and loop through each file using some sort of for loop?
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In Clojure how can I convert a String to a number?
...ew answer
I like snrobot's answer better. Using the Java method is simpler and more robust than using read-string for this simple use case. I did make a couple of small changes. Since the author didn't rule out negative numbers, I adjusted it to allow negative numbers. I also made it so it requires ...
Get IP address of visitors using Flask for Python
I'm making a website where users can log on and download files, using the Flask micro-framework (based on Werkzeug ) which uses Python (2.6 in my case).
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How can I make the tabs work normally on Xcode 4?
...hey don't work like tabs in other popular IDEs (Visual Studio or Eclipse). And for me this kind of sucks.
In general, I expect IDE tabs to keep more than 1 file open. So if I click a file in the project tree, I expect that it will switch to the tab I have opened with that file - if I have already op...
TimeStamp on file name using PowerShell
... example, $() like so:
"C:\temp\mybackup $(get-date -f yyyy-MM-dd).zip"
And if you are getting the path from somewhere else - already as a string:
$dirName = [io.path]::GetDirectoryName($path)
$filename = [io.path]::GetFileNameWithoutExtension($path)
$ext = [io.path]::GetExtension($path)
$...
What is null in Java?
...ceof operator is true if the value of the RelationalExpression is not null and the reference could be cast to the ReferenceType without raising a ClassCastException. Otherwise the result is false.
This means that for any type E and R, for any E o, where o == null, o instanceof R is always false.
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What is the difference between a weak reference and an unowned reference?
...
Both weak and unowned references do not create a strong hold on the referred object (a.k.a. they don't increase the retain count in order to prevent ARC from deallocating the referred object).
But why two keywords? This distinction has...
C programming in Visual Studio
...t menu I can choose between Visual Basic, Visual C#, Visual C++, Visual F# and others but I don't see "C" or "Visual C".
6 ...
Google Map API V3: How to add Custom data to markers
...rmation to my markers for later use. There are ways to have an info-window and a title, but what If I want to associate the marker with other information.
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