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Possibility of duplicate Mongo ObjectId's being generated in two different collections?
Is it possible for the same exact Mongo ObjectId to be generated for a document in two different collections? I realize that it's definitely very unlikely, but is it possible?
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String concatenation: concat() vs “+” operator
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No, not quite.
Firstly, there's a slight difference in semantics. If a is null, then a.concat(b) throws a NullPointerException but a+=b will treat the original value of a as if it were null. Furthermore, the concat() method only accep...
Iterate two Lists or Arrays with one ForEach statement in C#
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This is known as a Zip operation and will be supported in .NET 4.
With that, you would be able to write something like:
var numbers = new [] { 1, 2, 3, 4 };
var words = new [] { "one", "two", "three", "four" };
var numbersAndWords = numbers.Zip(words, (n, w) => new { Number = n, Word = ...
Hash Map in Python
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edited Oct 23 '19 at 9:23
Reinout van Rees
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Xcode build failure “Undefined symbols for architecture x86_64”
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It looks like you are missing including the IOBluetooth.framework in your project. You can add it by:
-Clicking on your project in the upper left of the left pane (the blue icon).
-In the middle pane, click on the Build P...
What do *args and **kwargs mean? [duplicate]
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Putting *args and/or **kwargs as the last items in your function definition’s argument list allows that function to accept an arbitrary number of arguments and/or keyword arguments.
For example, if you wanted to write a function that returned the sum of all its ar...
How do I get the filepath for a class in Python?
... which file the class was defined in? I need something that can work from either the class C, or from an instance off C.
3 ...
Most efficient way to determine if a Lua table is empty (contains no entries)?
...icient way to determine if a table is empty (that is, currently contains neither array-style values nor dict-style values)?
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Reset C int array to zero : the fastest way?
Assuming that we have a T myarray[100] with T = int, unsigned int, long long int or unsigned long long int, what is the fastest way to reset all its content to zero (not only for initialization but to reset the content several times in my program)? Maybe with memset?
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How can I troubleshoot my Perl CGI script?
...is answer is intended as a general framework for working through
problems with Perl CGI scripts and originally appeared on Perlmonks as Troubleshooting Perl CGI Scripts. It is not a complete guide to every
problem that you may encounter, nor a tutorial on bug squashing. It
is just the culmination ...