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MongoDB Aggregation: How to get total records count?
... is one of the most commonly asked question to obtain the paginated result and the total number of results simultaneously in single query. I can't explain how I felt when I finally achieved it LOL.
$result = $collection->aggregate(array(
array('$match' => $document),
array('$group' => ...
Is it better to use std::memcpy() or std::copy() in terms to performance?
...ll have a slight, almost imperceptible performance loss. I just did a test and found that to be untrue: I did notice a performance difference. However, the winner was std::copy.
I wrote a C++ SHA-2 implementation. In my test, I hash 5 strings using all four SHA-2 versions (224, 256, 384, 512), and ...
How to avoid “cannot load such file — utils/popen” from homebrew on OSX
...al
If it still doesn't work, use these steps inside a terminal session and everything will be fine:
cd /usr/local/Library/Homebrew
git reset --hard
git clean -df
brew update
This may be because homebrew is not updated.
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Meaning of tilde in Linux bash (not home directory)
... `dirs +1`
~2 `dirs +2`
~-1 `dirs -1`
dirs and ~1, ~-1, etc., are used in conjunction with pushd and popd.
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Javascript parseInt() with leading zeros
...aScript treat strings starting with 0 as octal (when no base is specified) and neither 08 nor 09 are valid octal numbers.
From the Mozilla documentation:
If radix is undefined or 0, JavaScript assumes the following:
If the input string begins with "0x" or "0X", radix is 16
(hexadecim...
PHP equivalent of .NET/Java's toString()
...rs:
$myText = (string)$myVar;
There are more details for string casting and conversion in the Strings section of the PHP manual, including special handling for booleans and nulls.
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Create a custom event in Java
...dListener(responder);
initiater.sayHello(); // Prints "Hello!!!" and "Hello there..."
}
}
Related article: Java: Creating a custom event
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Ruby: kind_of? vs. instance_of? vs. is_a?
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kind_of? and is_a? are synonymous.
instance_of? is different from the other two in that it only returns true if the object is an instance of that exact class, not a subclass.
Example:
"hello".is_a? Object and "hello".kind_of? Obje...
Git submodule push
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Yes, and don't forget to pull changes from your synchronized local branch (if any) before pushing. Happens eg. when working with a gh-pages branch for documentation on a github repo :)
– NiKo
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What do (lambda) function closures capture?
Recently I started playing around with Python and I came around something peculiar in the way closures work. Consider the following code:
...