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Distinct() with lambda?
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IEnumerable<Customer> filteredList = originalList
.GroupBy(customer => customer.CustomerId)
.Select(group => group.First());
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Test whether a glob has any matches in bash
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If find feels like overkill and the number of files likely to match is small, use stat:
if stat -t glob* >/dev/null 2>&1
then
echo found
else
echo not found
fi
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Difference between style = “position:absolute” and style = “position:relative”
...ive positioning, on the other hand, is just like stating no positioning at all, but the left, right, top and bottom attributes "nudge" the element out of their normal layout. The rest of the elements on the page still get laid out as if the element was in its normal spot though.
For example, if I h...
What is more efficient: Dictionary TryGetValue or ContainsKey+Item?
...ll be faster.
ContainsKey uses the same check as TryGetValue, which internally refers to the actual entry location. The Item property actually has nearly identical code functionality as TryGetValue, except that it will throw an exception instead of returning false.
Using ContainsKey followed by t...
When to use self over $this?
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$x = new Y();
$x->bar();
?>
The idea is that $this->foo() calls the foo() member function of whatever is the exact type of the current object. If the object is of type X, it thus calls X::foo(). If the object is of type Y, it calls Y::foo(). But with self::foo(), X::foo() is always ...
What are best practices for validating email addresses on iOS 2.0
... ; "]", or "\"
Yes, that means +, ', etc are all legit.
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List or IList [closed]
...u are exposing your class through a library that others will use, you generally want to expose it via interfaces rather than concrete implementations. This will help if you decide to change the implementation of your class later to use a different concrete class. In that case the users of your lib...
Cross-thread operation not valid: Control accessed from a thread other than the thread it was create
...stage
if(InvokeRequired)
{
// after we've done all the processing,
this.Invoke(new MethodInvoker(delegate {
// load the control with the appropriate data
}));
return;
}
}
}
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How to permanently remove few commits from remote branch
...ushing it)
This SO answer illustrates the danger of such a command, especially if people depends on the remote history for their own local repos.
You need to be prepared to point out people to the RECOVERING FROM UPSTREAM REBASE section of the git rebase man page
With Git 2.23 (August 2019, nine...
Programmatically set the initial view controller using Storyboards
How do I programmatically set the InitialViewController for a Storyboard? I want to open my storyboard to a different view depending on some condition which may vary from launch to launch.
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