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Update MongoDB field using value of another field
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The best way to do this is in version 4.2+ which allows using of aggregation pipeline in the update document and the updateOne, updateMany or update collection method. Note that the latter has been deprecated in most if not all languages drivers.
MongoDB 4.2+
Version 4.2 ...
Handlebars.js Else If
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{{#if FriendStatus.IsFriend}}
<div class="ui-state-default ui-corner-all" title=".ui-icon-mail-closed"><span class="ui-icon ui-icon-mail-closed"></span></div>
{{else if FriendStatus.FriendRequested}}
<div class="ui-state-default ui-corner-all" title=".ui-icon-check"&g...
Union Vs Concat in Linq
...mpare references of items. Your items have different references, thus they all are considered different. When you cast to base type X, reference is not changed.
If you will override Equals and GetHashCode (used to select distinct items), then items will not be compared by reference:
class X
{
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How to get everything after a certain character?
...te fast.
$s = '233718_This_is_a_string';
$firstPart = strtok( $s, '_' );
$allTheRest = strtok( '' );
Empty string like this will force the rest of the string to be returned.
NB if there was nothing at all after the '_' you would get a FALSE value for $allTheRest which, as stated in the document...
Rename multiple files in a directory in Python [duplicate]
...e script itself. Instead of using . as the dir, you could make a variable called dir and use that, then prepend dir to the filename.
– styfle
May 18 '11 at 5:53
18
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Ternary operator is twice as slow as an if-else block?
...several additional registers available, and each register is 64-bits. This allows the X64 JIT to perform the inner loop entirely using registers aside from loading i from the array, while the X86 JIT places several stack operations (memory access) in the loop.
value is a 64-bit integer, which requir...
Concurrent HashSet in .NET Framework?
...ass.
private ConcurrentBag<string> _data;
Self-implementation
Finally, as you did, you can implement your own data type, using lock or other ways that the .NET provides you to be thread-safe. Here is a great example: How to implement ConcurrentHashSet in .Net
The only drawback of this sol...
Python ElementTree module: How to ignore the namespace of XML files to locate matching element when
I want to use the method of "findall" to locate some elements of the source xml file in the ElementTree module.
10 Answers
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UITextView that expands to text using auto layout
I have a view that is laid out completely using auto layout programmatically. I have a UITextView in the middle of the view with items above and below it. Everything works fine, but I want to be able to expand UITextView as text is added. This should push everything below it down as it expands.
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HTML 5 Favicon - Support?
.../to/favicon.png">
This icon should be 196x196 pixels in size to cover all devices that may use this icon.
To cover touch icons on mobile devices we are going to use Apple's proprietary way to cite a touch icon:
<link rel="apple-touch-icon-precomposed" href="apple-touch-icon-precomposed.pn...