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Empty arrays seem to equal true and false at the same time
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You're testing different things here.
if (arr) called on object (Array is instance of Object in JS) will check if the object is present, and returns true/false.
When you call if (arr == false) you compare values of this object and the primitive false value. Internally, a...
How do I create a new Swift project without using Storyboards?
Creating a new project in XCode 6 doesn't allow to disable Storyboards. You can only select Swift or Objective-C and to use or not Core Data.
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URLWithString: returns nil
...llowing API webStringURL = [stringURL stringByAddingPercentEncodingWithAllowedCharacters:NSCharacterSet.URLQueryAllowedCharacterSet];
– Rushabh
Oct 24 '17 at 0:37
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Android: How to stretch an image to the screen width while maintaining aspect ratio?
... always roughly square) and display it so that it fills the screen horizontally, and stretches vertically to maintain the aspect ratio of the image, on any screen size. Here is my (non-working) code. It stretches the image horizontally, but not vertically, so it is squashed...
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What is a semaphore?
...s bouncers at a nightclub. There are a dedicated number of people that are allowed in the club at once. If the club is full no one is allowed to enter, but as soon as one person leaves another person might enter.
It's simply a way to limit the number of consumers for a specific resource. For exampl...
How can I select rows with most recent timestamp for each key value?
...aster than other answers, at least in my case.
– rain_
Sep 6 '17 at 7:51
@rain_ It really depends on the use case. The...
What actually causes a Stack Overflow error? [duplicate]
...ve programs, when there is a risk of writing into memory that had not been allocated for the buffer, and thus to corrupt some other memory locations. It's not the case at all.
JVM has a given memory allocated for each stack of each thread, and if an attempt to call a method happens to fill this mem...
What's the state of the art in email validation for Rails?
... answered Aug 24 '10 at 9:56
HallelujahHallelujah
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Is there a way to make R beep/play a sound at the end of a script?
...ion sounds in R which should work cross-platform. Run the following to install beepr and make a sound:
install.packages("beepr")
library(beepr)
beep()
More info at github: https://github.com/rasmusab/beepr
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Are memory leaks ever ok? [closed]
...forced this situation on me, it would lead me to seriously suspect the overall quality of the library in question. It would be as if I test drove a car and found a couple loose washers and nuts in one of the cupholders – it may not be a big deal in itself, but it portrays a lack of commitment to ...