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LINQ: Distinct values
...
IEqualityComparer<TKey> comparer)
{
HashSet<TKey> knownKeys = new HashSet<TKey>(comparer);
foreach (TSource element in source)
{
if (knownKeys.Add(keySelector(element)))
{
yield return element;
}
}
}
(If you pass...
How do I create delegates in Objective-C?
I know how delegates work, and I know how I can use them.
19 Answers
19
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Getting “unixtime” in Java
...a 8 you can use
import java.time.Instant
...
long unixTimestamp = Instant.now().getEpochSecond();
Instant.now() returns an Instant that represents the current system time. With getEpochSecond() you get the epoch seconds (unix time) from the Instant.
...
How do I find the length of an array?
...pression so it doesn't have any drawbacks over the macro (at least none I know of).
You can also consider using std::array from C++11 which exposes its length with no overhead over a native C array.
C++17 has std::size() in the <iterator> header which does the same and works for STL containe...
PHP foreach change original array values
...ference (&) is ... controversial. I recommend not using it unless you know why you need it and test the results.
I would recommend doing the following:
foreach ($fields as $key => $field) {
if ($field['required'] && strlen($_POST[$field['name']]) <= 0) {
$fields[$key]...
How do I create a self-signed certificate for code signing on Windows?
...ndows Server 2012, Windows Server 2012 R2, or Windows 8.1 then MakeCert is now deprecated, and Microsoft recommends using the PowerShell Cmdlet New-SelfSignedCertificate.
If you're using an older version such as Windows 7, you'll need to stick with MakeCert or another solution. Some people suggest ...
How does the SQL injection from the “Bobby Tables” XKCD comic work?
...call it Derper) are concatenated with the rest of the query, the result is now actually two queries separated by the statement terminator (semicolon). The second query has been injected into the first. When the code executes this query against the database, it will look like this
INSERT INTO Stud...
Unlink of file failed
...was not friendly to systems that cannot remove files that are open.
They now close the packs before doing so.
That fixes git-for-widows issue 500.
Looking at the test used to validate that new approach, a possible workaround (since Git 2.8 is not yet out) would be to raise artificially gc.autoP...
Accessing MP3 metadata with Python [closed]
...answered Sep 19 '08 at 14:30
OwenOwen
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mingw-w64 threads: posix vs win32
... on Windows and there are two options: win32 threads and posix threads. I know what is the difference between win32 threads and pthreads but I don't understand what is the difference between these two options. I doubt that if I will choose posix threads it will prevent me from calling WinAPI functio...