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What is an optional value in Swift?
...long with Generics) are one of the most difficult Swift concepts to understand. Because of how they are written and used, it's easy to get a wrong idea of what they are. Compare the optional above to creating a normal String:
var name: String = "Bertie" // No "?" after String
From the syntax it loo...
How do pointer to pointers work in C?
...
Let's assume an 8 bit computer with 8 bit addresses (and thus only 256 bytes of memory). This is part of that memory (the numbers at the top are the addresses):
54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69
+----+----+----+----+----+----+----+...
Android Studio with Google Play Services
I'm trying to test Google Play Services with the new Android Studio.
I have a project with a dependency to the google_play_services.jar.
But when I try to Rebuild the project I get the following errors:
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How do I get a Cron like scheduler in Python? [closed]
I'm looking for a library in Python which will provide at and cron like functionality.
9 Answers
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What's the difference between design patterns and architectural patterns?
...ou find in programs. It allows us to deconstruct a large complex structure and build using simple parts. It provides a general solution for a class of problems.
A large complex software goes through a series of deconstruction at different levels. At large level, architectural patterns are the tool...
What's the fastest way to merge/join data.frames in R?
...he first. If there are duplicates in the second data frame then the match and merge approaches are not the same. Match is, of course, faster since it is not doing as much. In particular it never looks for duplicate keys. (continued after code)
DF1 = data.frame(a = c(1, 1, 2, 2), b = 1:4)
DF2 = da...
SQL Server - copy stored procedures from one db to another
I am new to SQL, and what I needed to do was to combine 2 .mdf databases into one. I did that using SQL Server 2008 Manager - Tasks > Import/Export tables.The tables and views were copied successfully, but there are no Stored procedures in the new database. Is there any way to do that?
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How to put a UserControl into Visual Studio toolBox
I made a usercontrol in my project, and after building project, I need to put it in my toolbox, and use it as a common control. but i can't. the UserControl is in my project namespace, and I tried Choose Item in right click menu, but I didn't find a way to add it.
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What does SynchronizationContext do?
...alling the static SynchronizationContext.SetSynchronizationContext method, and the current context of the running thread can be queried via the SynchronizationContext.Current property.
Despite what I just wrote (each thread having an associated synchronization context), a SynchronizationContext does...
How can I prevent the scrollbar overlaying content in IE10?
In IE10, the scrollbar is not always there... and when it appears it comes on as an overlay... It's a cool feature but I would like to turn it off for my specific website as it is a full screen application and my logos and menus are lost behind it.
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