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Is “else if” a single keyword?
...er to Can you start a class name with a numeric digit? that spaces are not allowed in identifiers and so therefore else if can not be a single keyword but must be two separate keywords.
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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 ...
Create a matrix of scatterplots (pairs() equivalent) in ggplot2
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community wiki
3 revs, 3 users 88%naught101
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Returning anonymous type in C#
...ToList();
}
}
http://msdn.microsoft.com/en-us/library/system.tuple(v=vs.110).aspx
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Generic deep diff between two objects
... },
isFunction: function (x) {
return Object.prototype.toString.call(x) === '[object Function]';
},
isArray: function (x) {
return Object.prototype.toString.call(x) === '[object Array]';
},
isDate: function (x) {
return Object.prototype.toString.call(x) === '[ob...
How to count the number of set bits in a 32-bit integer?
...Hamming Weight', 'popcount' or 'sideways addition'.
The 'best' algorithm really depends on which CPU you are on and what your usage pattern is.
Some CPUs have a single built-in instruction to do it and others have parallel instructions which act on bit vectors. The parallel instructions (like x86's ...
What is the difference between #include and #include “filename”?
...e> the preprocessor searches in an implementation dependent manner, normally in search directories pre-designated by the compiler/IDE. This method is normally used to include standard library header files.
For #include "filename" the preprocessor searches first in the same directory as the file ...
How to grab substring before a specified character jQuery or JavaScript
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For performance comparison, see: jsperf.com/street-array-vs-substr
– Goodbye StackExchange
Nov 30 '17 at 13:17
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Which is more efficient: Multiple MySQL tables or one large table?
I store various user details in my MySQL database. Originally it was set up in various tables meaning data is linked with UserIds and outputting via sometimes complicated calls to display and manipulate the data as required. Setting up a new system, it almost makes sense to combine all of these tabl...
What does “program to interfaces, not implementations” mean?
...t worried about implementation and the interface signature determines what all operations can be done. This can be used to change the behavior of a program at run-time. It also helps you to write far better programs from the maintenance point of view.
Here's a basic example for you.
public enum La...