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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
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Why is [1,2] + [3,4] = “1,23,4” in JavaScript?
...t how the + operator behaves in general also.
So, here it goes.
Excluding E4X and implementation-specific stuff, Javascript (as of ES5) has 6 built-in data types:
Undefined
Null
Boolean
Number
String
Object
Note that although typeof somewhat confusingly returns object for Null and function for cal...
Synchronously waiting for an async operation, and why does Wait() freeze the program here
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How to get device make and model on iOS?
...ing if it's possible to detect/know if I have an iPhone 3GS vs. and iPhone 4 vs. an iPhone 4S (in actuality, all I really want to do is determine if I have a 3G or not, because I'm doing fairly graphics intensive stuff) .
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MySQL 'create schema' and 'create database' - Is there any difference
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140
The documentation of MySQL says :
CREATE DATABASE creates a database
with the given name...
Argparse optional positional arguments?
... techtonik
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answered Dec 18 '10 at 21:15
Vinay SajipVinay Sajip
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Are static class instances unique to a request or a server in ASP.NET?
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Your static classes and static instance fields are shared between all requests to the applicati...
What does “atomic” mean in programming?
...of type long. The following operation is not an atomic operation:
foo = 65465498L;
Indeed, the variable is written using two separate operations: one that writes the first 32 bits, and a second one which writes the last 32 bits. That means that another thread might read the value of foo, and see ...
Is is possible to check if an object is already attached to a data context in Entity Framework?
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answered Nov 11 '09 at 15:54
joshcomleyjoshcomley
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