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Test whether a Ruby class is a subclass of another class
I would like to test whether a class inherits from another class, but there doesn't seem to exist a method for that.
2 Answ...
A list of indices in MongoDB?
...
From the shell:
db.test.getIndexes()
For shell help you should try:
help;
db.help();
db.test.help();
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Why can I create a class named “var”?
...r is not a keyword according to this list.
it is a contextual keyword, so from the context the compiler is able to decide which is your class and which is the contextual keyword, and no confusion arises.
a contextual keyword is:
used to provide a specific meaning in the code, but it is not a
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in iPhone App How to detect the screen resolution of the device
...e" bundle:nil];
// Instantiate the initial view controller object from the storyboard
UIViewController *initialViewController = [iPhone35Storyboard instantiateInitialViewController];
// Instantiate a UIWindow object and initialize it with the screen size of the iOS device
...
How can I get the current date and time in UTC or GMT in Java?
...re flexible formatting, or other additional features, then apply an offset-from-UTC of zero, for UTC itself (ZoneOffset.UTC constant) to get a OffsetDateTime.
OffsetDateTime now = OffsetDateTime.now( ZoneOffset.UTC );
Dump to console…
System.out.println( "now.toString(): " + now );
When run...
Mixed mode assembly is built against version ‘v2.0.50727′ of the runtime
...
Enabling the legacy from app.config didn't work for me. For unknown reasons, my application wasn't activating V2 runtime policy. I found a work around here.
Enabling the legacy from app.config is a recommended approach but in some cases it does...
What's the reason I can't create generic array types in Java?
...s to explain the same thing I've already said, the only thing that changed from my original reason is that I though that he said T[] ts = new T[n]; was a valid example. I'll keep the vote because he's answer can cause issues and confusions to other devs and is also off-topic. Also, I'll stop comment...
If I revoke an existing distribution certificate, will it mess up anything with existing apps?
...re or existing apps. Once
you revoke your certificate, it will be deleted from the list of certificates. Revocation
has these effects:
You can no longer build apps in Xcode using provision profiles containing the revoked
certificate.
You can no longer submit apps to the App Store that were signe...
Is there a way to specify how many characters of a string to print out using printf()?
...rintf(), which treats the '*' in the format as a request to get the length from an argument.
You can also use the notation:
printf ("Here are the first 8 chars: %*.*s\n",
8, 8, "A string that is more than 8 chars");
This is also analogous to the "%8.8s" notation, but again allows you to ...
std::shared_ptr thread safety explained
...
Yes. From my understanding, the standard does not say that it must be lock-free. But in the latest GCC and MSVC, it is lock-free on Intel x86 hardware, and I think other good compilers are likely to do the same when the hardware ...