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How do I cast a variable in Scala?
...
The preferred technique is to use pattern matching. This allows you to gracefully handle the case that the value in question is not of the given type:
g match {
case g2: Graphics2D => g2
case _ => throw new ClassCastException
}
This block replicates the semantics of th...
Can you supply arguments to the map(&:method) syntax in Ruby?
... the shorthand block:
[['0', '1'], ['2', '3']].map(&:map.with(&:to_i))
# => [[0, 1], [2, 3]]
[%w(a b), %w(c d)].map(&:inject.with(&:+))
# => ["ab", "cd"]
[(1..5), (6..10)].map(&:map.with(&:*.with(2)))
# => [[2, 4, 6, 8, 10], [12, 14, 16, 18, 20]]
Here is a conve...
“From View Controller” disappears using UIViewControllerContextTransitioning
... goes black. The key UIWindow is completely empty – no view hierarchy at all!
I played around a bit and it looks like there is an easy workaround, for simple cases. You can just re-add the toViewController's view as a subview of the key window's:
transitionContext.completeTransition(true)
UIAp...
How do I test a private function or a class that has private methods, fields or inner classes?
...mework.
@Jailbreak Foo foo = new Foo();
// Direct, *type-safe* access to *all* foo's members
foo.privateMethod(x, y, z);
foo.privateField = value;
This way your code remains type-safe and readable. No design compromises, no overexposing methods and fields for the sake of tests.
If you have...
Why the switch statement cannot be applied on strings?
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The reason why has to do with the type system. C/C++ doesn't really support strings as a type. It does support the idea of a constant char array but it doesn't really fully understand the notion of a string.
In order to generate the code for a switch statement the compiler must under...
How do I allow HTTPS for Apache on localhost?
... up HTTPS with a self-signed cert on Apache on localhost, but how do I actually do that? I have no idea at all.
16 Answers
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How to find third or nth maximum salary from salary table?
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Use ROW_NUMBER(if you want a single) or DENSE_RANK(for all related rows):
WITH CTE AS
(
SELECT EmpID, EmpName, EmpSalary,
RN = ROW_NUMBER() OVER (ORDER BY EmpSalary DESC)
FROM dbo.Salary
)
SELECT EmpID, EmpName, EmpSalary
FROM CTE
WHERE RN = @NthRow
...
Where is Maven' settings.xml located on mac os?
...8:00)
Maven home: /usr/local/Cellar/maven/3.5.0/libexec
Java version: 1.8.0_121, vendor: Oracle Corporation
Java home: /Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre
Default locale: zh_CN, platform encoding: UTF-8
OS name: "mac os x", version: "10.11.5", arch: "x86_64", family:...
Should JAVA_HOME point to JDK or JRE?
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Is it possible to validate pro-grammatically whether the Java path is set as JRE or JDK?
– Dinesh Kumar P
Mar 2 '18 at 11:22
add a comment
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Crash logs generated by iPhone Simulator?
...ept trying a few things in the app and it kept crashing). The crashes were all the same, so it wasn't an issue, but I am wondering if this is generally the case?
– Samik R
Dec 8 '12 at 7:46
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