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What is a Portable Class Library?
...uts any other answer here in the shade.
UPDATE May 20 2013:
Very practical coverage of practical application and implications of this for cross-device stuff (think Xamarin Studio) in Tablet Show podcast with Atley Hunter. Key takeaway:- PCLs are a very useful constraint to impose on onself in cr...
How to create a unique index on a NULL column?
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Pretty sure you can't do that, as it violates the purpose of uniques.
However, this person seems to have a decent work around:
http://sqlservercodebook.blogspot.com/2008/04/multiple-null-values-in-unique-index-in.html
...
JavaScript: Class.method vs. Class.prototype.method
... no relationship with an object instance of that constructor function, you can consider it like a 'static method'.
In JavaScript functions are first-class objects, that means you can treat them just like any object, in this case, you are only adding a property to the function object.
The second fu...
Which characters need to be escaped in HTML?
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If you're inserting text content in your document in a location where text content is expected1, you typically only need to escape the same characters as you would in XML. Inside of an element, this just includes the entity escape ampersand & and the element delimiter less-than...
E731 do not assign a lambda expression, use a def
...irst form means that the name of the resulting
function object is specifically 'f' instead of the generic '<lambda>'.
This is more useful for tracebacks and string representations in
general. The use of the assignment statement eliminates the sole
benefit a lambda expression can offer ...
What does this square bracket and parenthesis bracket notation mean [first1,last1)?
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∞ isn't an ordinal number, of the sort that you can do arithmetic with. But it's a valid cardinal number when answering questions like "How many integers are there?". It's also, as in this case, perfectly valid as a limit
– Kevin Wright
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What's the idiomatic syntax for prepending to a short python list?
...f a list, python has to move all the other items one space forwards, lists can't "make space at the front". collections.deque (double ended queue) has support for "making space at the front" and is much faster in this case.
– fejfo
Mar 18 at 14:49
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How do browsers pause/change Javascript when tab or window is not active?
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Test One
I have written a test specifically for this purpose:
Frame Rate Distribution: setInterval vs requestAnimationFrame
Note: This test is quite CPU intensive. requestAnimationFrame is not supported by IE 9- and Opera 12-.
The test logs the actual time it t...
Why can't the C# constructor infer type?
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Is there a philosophical reason why the constructor can't support type inference?
No. When you have
new Foo(bar)
then we could identify all types called Foo in scope regardless of generic arity, and then do overload resolution on each using ...
What's the role of GetHashCode in the IEqualityComparer in .NET?
...n of the object. Since there is no limit to how much information an object can contain, certain hash codes are shared by multiple objects - so the hash code is not necessarily unique.
A dictionary is a really cool data structure that trades a higher memory footprint in return for (more or less) co...