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Most lightweight way to create a random string and a random hexadecimal number

...165037870407104 9.0292739868164062 5.2836320400238037 t3 only makes one call to the random module, doesn't have to build or read a list, and then does the rest with string formatting. share | impr...
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How do I implement an Objective-C singleton that is compatible with ARC?

...n; dispatch_once(&onceToken, ^{ sharedInstance = [[MyClass alloc] init]; // Do any other initialisation stuff here }); return sharedInstance; } share | improve this ...
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How to find index of list item in Swift?

...B = arr.indexOf("b") // 1 let indexOfD = arr.indexOf("d") // nil Additionally, finding the first element in an array fulfilling a predicate is supported by another extension of CollectionType: let arr2 = [1,2,3,4,5,6,7,8,9,10] let indexOfFirstGreaterThanFive = arr2.indexOf({$0 > 5}) // 5 let i...
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Converting from a string to boolean in Python?

... Use: bool(distutils.util.strtobool(some_string)) Python 2: http://docs.python.org/2/distutils/apiref.html?highlight=distutils.util#distutils.util.strtobool Python 3: https://docs.python.org/3/distutils/apiref.html#distutils.util.strtobool True values are y...
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How do I launch the Android emulator from the command line?

...h it, but you don't have any AVDs created and have to use command line for all the actions. You have to do the following. Create a new virtual device (AVD) for the platform you need. If you have to use command line for creating your AVD, you can call android create avd -n <name> -t <targe...
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How can I determine if a variable is 'undefined' or 'null'?

...enceError and break execution if variable is not defined or referred to at all in the code, using typeof is safer. – Mani Gandham Jun 15 '14 at 9:49 59 ...
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Get push notification while App in foreground iOS

... app received push notifications in foreground func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) { completionHandler([.alert, .badge, .sound...
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Process escape sequences in a string in Python

...ything in the pattern 'string escape', 'string@escape" and whatnot... basically 'string\W+escape' – Nas Banov Oct 26 '10 at 5:18 ...
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Understanding MongoDB BSON Document size limit

... First off, this actually is being raised in the next version to 8MB or 16MB ... but I think to put this into perspective, Eliot from 10gen (who developed MongoDB) puts it best: EDIT: The size has been officially 'raised' to 16MB So, on your...
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How do I disable the “Press ENTER or type command to continue” prompt in Vim?

... I'm not sure how to do it globally though for one command: :silent !<command> Be sure to include a space after silent share | improve this answe...