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How can I use Timer (formerly NSTimer) in Swift?
...iewDidLoad()
// Swift block syntax (iOS 10+)
let timer = Timer(timeInterval: 0.4, repeats: true) { _ in print("Done!") }
// Swift >=3 selector syntax
let timer = Timer.scheduledTimer(timeInterval: 0.4, target: self, selector: #selector(self.update), userInfo: nil, repeats: true)
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Fast ceiling of an integer division in C / C++
Given integer values x and y , C and C++ both return as the quotient q = x/y the floor of the floating point equivalent. I'm interested in a method of returning the ceiling instead. For example, ceil(10/5)=2 and ceil(11/5)=3 .
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How do I kill background processes / jobs when my shell script exits?
I am looking for a way to clean up the mess when my top-level script exits.
13 Answers
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What to use instead of “addPreferencesFromResource” in a PreferenceActivity?
I just noticed the fact that the method addPreferencesFromResource(int preferencesResId) is marked deprecated in Android's documentation ( Reference Entry ).
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Replacing spaces with underscores in JavaScript?
I'm trying to use this code to replace spaces with _, it works for the first space in the string but all the other instances of spaces remain unchanged. Anybody know why?
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How to design a database for User Defined Fields?
... the data distribution and access patterns described.
Pros:
Because you indicate that some UDFs
have values for a small portion of
the overall data set, a separate
table would give you the best
performance because that table will
be only as large as it needs to be
to support the UDF. The same hol...
Advantages of Binary Search Trees over Hash Tables
What are the advantages of binary search trees over hash tables?
18 Answers
18
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PostgreSQL DISTINCT ON with different ORDER BY
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Documentation says:
DISTINCT ON ( expression [, ...] ) keeps only the first row of each set of rows where the given expressions evaluate to equal. [...] Note that the "first row" of each set is unpredictable unless ORDER BY is used to ensure that th...
Mercurial error: abort no username supplied
Problem on WindowsXP (likely will happen on all Win installs), first time using Mercurial. I found the answer in an inobvious place so I'm asking/answering the question myself so others don't have to search like I did.
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LINQ to Entities does not recognize the method 'System.String ToString()' method, and this method ca
I'm migrating some stuff from one mysql server to a sql server but i can't figure out how to make this code work:
11 Answer...