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What is the difference between single-quoted and double-quoted strings in PHP?
...uding some regexes), and variables in the strings will be evaluated. An important point here is that you can use curly braces to isolate the name of the variable you want evaluated. For example let's say you have the variable $type and you want to echo "The $types are". That will look for the variab...
Mutex example / tutorial? [closed]
I'm new to multithreading, and was trying to understand how mutexes work. Did a lot of Googling but it still left some doubts of how it works because I created my own program in which locking didn't work.
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Is it possible to do a sparse checkout without checking out the whole repository first?
I'm working with a repository with a very large number of files that takes hours to checkout. I'm looking into the possibility of whether Git would work well with this kind of repository now that it supports sparse checkouts but every example that I can find does the following:
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Measure elapsed time in Swift
How can we measure the time elapsed for running a function in Swift? I am trying to display the elapsed time like this: "Elapsed time is .05 seconds". Saw that in Java , we can use System.nanoTime(), is there any equivalent methods are available in Swift to accomplish this?
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What is the easiest way to get current GMT time in Unix timestamp format?
...fferent packages ( datetime , time , calendar ) as can be seen here in order to deal with time. I made a big mistake by using the following to get current GMT time time.mktime(datetime.datetime.utcnow().timetuple())
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How do you create a read-only user in PostgreSQL?
...public TO xxx;
This only affects tables that have already been created. More powerfully, you can automatically have default roles assigned to new objects in future:
ALTER DEFAULT PRIVILEGES IN SCHEMA public
GRANT SELECT ON TABLES TO xxx;
Note that by default this will only affect objects (ta...
Key hash for Android-Facebook app
I'm working on an Android app, in which I want to integrate a Facebook
posting feature. I downloaded the Facebook-Android SDK, and I got
the readme.md (text file) in there, in which it is mentioned to generate
the key hash for Android. How do I generate it?
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Java: Static Class?
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Private constructor and static methods on a class marked as final.
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Max size of an iOS application
...is the maximum size your iOS app can be.
As of January 26, 2017
App Size for iOS (& tvOS) only
Your app’s total uncompressed size must be less than 4GB. Each Mach-O executable file (for example, app_name.app/app_name) must not exceed these limits:
For apps whose MinimumOSVersion is less than...
How to delete a row by reference in data.table?
...le can add and delete columns by reference since it over-allocates the vector of column pointers, as you know. The plan is to do something similar for rows and allow fast insert and delete. A row delete would use memmove in C to budge up the items (in each and every column) after the deleted rows. D...