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MongoDB: Find a document by non-existence of a field?
...t -- thanks. I know this caveat holds true in MongoDB version 1.8.x and before; but I thought queries with $exists field constraints can now make use of indexes in version 2.0 ...?
– dampier
Dec 20 '11 at 1:57
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What is the Swift equivalent of -[NSObject description]?
...le protocol and then also implement a string property called description.
For example:
class MyClass: CustomStringConvertible {
let foo = 42
var description: String {
return "<\(type(of: self)): foo = \(foo)>"
}
}
print(MyClass()) // prints: <MyClass: foo = 42>
...
Is \d not supported by grep's basic expressions?
...is (iirc) POSIX regex, and \d is pcre. You can either pass -P to gnu grep, for perl-like regexps, or use [[:digit:]] instead of \d.
daenyth@Bragi ~ $ echo 1 | grep -P '\d'
1
daenyth@Bragi ~ $ echo 1 | grep '[[:digit:]]'
1
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Difference between compile and runtime configurations in Gradle
... artifacts needed at compile time are a subset of those needed at runtime. For example, let's say that a program called app uses library foo, and library foo internally uses library bar. Then only foo is needed to compile app, but both foo and bar are needed to run it. This is why by default, everyt...
Outputting data from unit test in python
...ware of the ability to create a customized message, which can carry some information, but sometimes you might deal with more complex data, that can't easily be represented as a string.
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How to show particular image as thumbnail while implementing share on Facebook?
...emselves pointed out that using the link rel attribute doesn't always work for some people. I find the meta property="og:image" to be much more reliable. The answer below should be the correct one.
– Dwayne Charrington
Feb 11 '11 at 1:11
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Python, add trailing slash to directory string, os independently
How can I add a trailing slash ( / for *nix, \ for win32) to a directory string, if the tailing slash is not already there? Thanks!
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NSLog the method name with Objective-C in iPhone
... since Apple could change it in an OS update.
– Nick Forge
May 5 '10 at 8:06
5
Yes, NSStringFromS...
Visual Studio Wcf Test Client - entering an Int array
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Difference between doseq and for in Clojure
What's the difference between doseq and for in Clojure? What are some examples of when you would choose to use one over the other?
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