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Why does direction of index matter in MongoDB?
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MongoDB concatenates the compound key in some way and uses it as the key in a BTree.
When finding single items - The order of the nodes in the tree is irrelevant.
If you are returning a range of nodes - The elements close to each other will be down the same branches of th...
How do I execute a string containing Python code in Python?
...ting code should generally be the position of last resort: It's slow, ugly and dangerous if it can contain user-entered code. You should always look at alternatives first, such as higher order functions, to see if these can better meet your needs.
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Quickly find whether a value is present in a C array?
...ate through an array of size 256 (preferably 1024, but 256 is the minimum) and check if a value matches the arrays contents. A bool will be set to true is this is the case.
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Why do we need boxing and unboxing in C#?
Why do we need boxing and unboxing in C#?
11 Answers
11
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Capitalize only first character of string and leave others alone? (Rails)
I'm trying to get Rails to capitalize the first character of a string, and leave all the others the way they are. I'm running into a problem where "i'm from New York" gets turned into "I'm from new york."
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How to create .ipa file using Xcode?
...lick Product > Archive > once this is complete open up the Organiser and click the latest version.
Step 3:
Click on Export... option from right side of organiser window.
Step 4:
Select a method for export > Choose correct signing > Save to Destination.
Xcode 10.0
Step 3:
From R...
How to remove elements from a generic list while iterating over it?
...er pattern for working with a list of elements which each need processed and then depending on the outcome are removed from the list.
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nonlocal keyword in Python 2.x
I'm trying to implement a closure in Python 2.6 and I need to access a nonlocal variable but it seems like this keyword is not available in python 2.x. How should one access nonlocal variables in closures in these versions of python?
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Merge multiple lines (two blocks) in Vim
I'd like to merge two blocks of lines in Vim, i.e. take lines n..m and append them to lines a..b . If you prefer a pseudocode explanation: [a[i] + b[i] for i in min(len(a), len(b))]
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How can I create directory tree in C++/Linux?
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With C++17 or later, there's the standard header <filesystem> with
function
std::filesystem::create_directories
which should be used in modern C++ programs.
The C++ standard functions do not have the POSIX-specific explicit
permissions (mode) argument, t...