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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?
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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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Get URL query string parameters
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The PHP way to do it is using the function parse_url, which parses a URL and return its components. Including the query string.
Example:
$url = 'www.mysite.com/category/subcategory?myqueryhash';
echo parse_url($url, PHP_URL_QUERY); # output "myqueryhash"
Full documentation here
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SVN: Ignore some directories recursively
... well as svn:ignore - can you provide a summary of these different options and how they compare? How does the --recursive flag affect them too?
– Dai
Mar 10 '17 at 21:29
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Setting a system environment variable from a Windows batch file?
...s it possible to set a environment variable at the system level from a command prompt in Windows 7 (or even XP for that matter). I am running from an elevated command prompt.
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DropDownList in MVC 4 with Razor
...w what model to call? Where does "tipo" come from?
– Andre
Feb 2 '18 at 10:38
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@Andre It's the n...
How to convert date to timestamp in PHP?
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This method works on both Windows and Unix and is time-zone aware, which is probably what you want if you work with dates.
If you don't care about timezone, or want to use the time zone your server uses:
$d = DateTime::createFromFormat('d-m-Y H:i:s', '22-09...
Convert a float64 to an int in Go
... a string. I know I can use fmt.Sprintf to convert anything to a string, and then strconv it to the data type I need, but this extra conversion seems a bit clumsy - is there a better way to do this?
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