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How is Generic Covariance & Contra-variance Implemented in C# 4.0?
...ch only ever lets you take values "out" of it - it doesn't let you add new ones. That will become IEnumerable<out T>. That doesn't hurt type safety at all, but lets you return an IEnumerable<string> from a method declared to return IEnumerable<object> for instance.
Contravariance ...
Accessing the web page's HTTP Headers in JavaScript
...y work if the response values you need are guaranteed to be identical from one request to the next. It will depend on your application, so your mileage with an approach like this will vary.
– keparo
Aug 17 '13 at 2:21
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How to apply multiple styles in WPF
...arate style which I would like to add to it without blowing away the first one. The styles have different TargetTypes, so I can't just extend one with the other.
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Visual Studio: How can I see the same file in two separate tab groups?
I want to be able to edit one method while looking at another method in the same file, as reference.
Can this be done?
8 An...
What does .SD stand for in data.table in R
...1 col: y
and operates on them in turn.
While it is operating on either one, it lets you refer to the current sub-data.table by using the nick-name/handle/symbol .SD. That's very handy, as you can access and operate on the columns just as if you were sitting at the command line working with a sin...
C# Entity-Framework: How can I combine a .Find and .Include on a Model Object?
... (SingleOrDefault), ToList will retrieve all entries first and then select one
– Sander Rijken
Sep 8 '11 at 13:51
5
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Is there an equivalent to background-size: cover and contain for image elements?
...eight: 100%; for portrait use max-width: 100%. Would be nice if there were one solution that worked for either landscape or portrait. Any ideas? This is the best cross-browser solution I've seen so far.
– terraling
Jul 20 '15 at 17:12
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Purpose of Python's __repr__
...repr__ should return a printable representation of the object, most likely one of the ways possible to create this object. See official documentation here. __repr__ is more for developers while __str__ is for end users.
A simple example:
>>> class Point:
... def __init__(self, x, y):
.....
When should I make explicit use of the `this` pointer?
...
@CamJackson: One can specialize classes on type: template<> struct A<float> { float x; };
– Macke
Dec 3 '14 at 7:33
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How to log a method's execution time exactly in milliseconds?
...o use mach_absolute_time, as shown in many of the other answers here. This one should be downvoted for being a bad example. See also the related answer that explains this all in more detail: stackoverflow.com/a/30363702/43615
– Thomas Tempelmann
Jun 4 '16 at 13...