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Does MongoDB's $in clause guarantee order
...d index order as shown.
If you need to preserve this order, then you basically have two options.
So let's say that you were matching on the values of _id in your documents with an array that is going to be passed in to the $in as [ 4, 2, 8 ].
Approach using Aggregate
var list = [ 4, 2, 8 ];
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Get class that defined method
...ited Jun 20 '14 at 19:44
Aaron Hall♦
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answered Jun 7 '09 at 2:23
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How to darken a background using CSS?
....png);
}
Reference: linear-gradient() - CSS | MDN
UPDATE: Not all browsers support RGBa, so you should have a 'fallback color'. This color will be most likely be solid (fully opaque) ex:background:rgb(96, 96, 96). Refer to this blog for RGBa browser support.
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What is uint_fast32_t and why should it be used instead of the regular int and uint32_t?
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int may be as small as 16 bits on some platforms. It may not be sufficient for your application.
uint32_t is not guaranteed to exist. It's an optional typedef that the implementation must provide iff it has an unsigned integer type of exactl...
Comparing two NumPy arrays for equality, element-wise
...two NumPy arrays for equality (where equality is defined as: A = B iff for all indices i: A[i] == B[i] )?
6 Answers
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How do I check for C++11 support?
...t have (partial) compiler-level support versus a standard C++ library with all the C++11 changes.
So Boost's defines mentioned in another answer remain the only sane way to figure out if there is, for example, support for C++11 threads and other specific parts of the standard.
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What is Autoloading; How do you use spl_autoload, __autoload and spl_autoload_register?
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spl_autoload_register() allows you to register multiple functions (or static methods from your own Autoload class) that PHP will put into a stack/queue and call sequentially when a "new Class" is declared.
So for example:
spl_autoload_register('m...
How to clear the interpreter console?
Like most Python developers, I typically keep a console window open with the Python interpreter running to test commands, dir() stuff, help() stuff , etc.
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What is the most efficient/elegant way to parse a flat table into a tree?
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Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentI...
Does Flask support regular expressions in its URL routing?
...will be evaluated directly at runtime. This shouldn't be problematic for smaller apps (or apps that reuse regex's multiple times, I'd think) as the last couple of regex patterns are stored compiled in memory.
– bbenne10
Jul 18 '13 at 14:13
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