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Cleaner way to update nested structures
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Zippers
Huet's Zipper provides convenient traversal and 'mutation' of an immutable data structure. Scalaz provides Zippers for Stream (scalaz.Zipper), and Tree (scalaz.TreeLoc). It turns out that the structure of the zipper is automatically derivable from the original data str...
What is the difference between '/' and '//' when used for division?
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In Python 3.x, 5 / 2 will return 2.5 and 5 // 2 will return 2. The former is floating point division, and the latter is floor division, sometimes also called integer division.
In Python 2.2 or later in the 2.x line, there is no difference for integers unless y...
What's the best practice for primary keys in tables?
...signing tables, I've developed a habit of having one column that is unique and that I make the primary key. This is achieved in three ways depending on requirements:
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Why is std::min failing when windows.h is included?
... (or more correctly, windef.h that it includes in turn) has macros for min and max which are interfering.
You should #define NOMINMAX before including it.
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How can I properly handle 404 in ASP.NET MVC?
.../shay/archive/2009/03/06/real-world-error-hadnling-in-asp-net-mvc-rc2.aspx and works in ASP.net MVC 1.0 as well
Here's how I handle http exceptions:
protected void Application_Error(object sender, EventArgs e)
{
Exception exception = Server.GetLastError();
// Log the exception.
ILogger ...
How To Get IPython Notebook To Run Python 3?
.... If you have any notebooks saved with python 2 then it will automatically convert them to Python 3 once you open the notebook.
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Ruby class instance variable vs. class variable
...mmon to that class without having sub-classes automatically also get them (and vice-versa). With class variables, you have the convenience of not having to write self.class from an instance object, and (when desirable) you also get automatic sharing throughout the class hierarchy.
Merging these t...
Is JavaScript an untyped language?
... talked about in one of the above answers - the runtime doesn't tag values and just treats each value as bits. JavaScript does tag values and has different behaviour based on those tags. So JavaScript obviously doesn't fit this category.
The other definition is from Programming Language Theory (the ...
Age from birthdate in python
How can I find an age in python from today's date and a persons birthdate? The birthdate is a from a DateField in a Django model.
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Detect Windows version in .net
...n't explicitly state that your exe assembly is compatible with Windows 8.1 and Windows 10.0, System.Environment.OSVersion will return Windows 8 version, which is 6.2, instead of 6.3 and 10.0! Source: here.
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