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What are dictionary view objects?
...sentially what their name says: views are simply like a window on the keys and values (or items) of a dictionary. Here is an excerpt from the official documentation for Python 3:
>>> dishes = {'eggs': 2, 'sausage': 1, 'bacon': 1, 'spam': 500}
>>> keys = dishes.keys()
>>>...
JavaScript: client-side vs. server-side validation
...k to the average user. For example, if they enter an invalid email address and move to the next field, you can show an error message immediately. That way the user can correct every field before they submit the form.
If you only validate on the server, they have to submit the form, get an error mes...
In Java, when should I create a checked exception, and when should it be a runtime exception? [dupli
When should I create a checked exception, and when should I make a runtime exception?
14 Answers
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What C++ Smart Pointer Implementations are available?
...ters shouldn't contain the same object. Assignment will transfer ownership and reset the rvalue auto pointer to a null pointer. Which leads to perhaps the worst drawback; they can't be used within STL containers due to the aforementioned inability to be copied. The final blow to any use case is they...
Does C# have extension properties?
...ot seen as valuable enough to be included in the previous versions of C# standard. C# 7 and C# 8.0 have seen this as proposal champion but it wasn't released yet, most of all because even if there is already an implementation, they want to make it right from the start.
But it will ...
There is an ...
Optimizing away a “while(1);” in C++0x
...oops?, although this is WG14 document the rationale applies to C++ as well and the document refers to both WG14 and WG21:
As N1509 correctly points out, the current draft essentially gives
undefined behavior to infinite loops in 6.8.5p6. A major issue for
doing so is that it allows code to m...
How do I delete a Git branch locally and remotely?
I want to delete a branch both locally and remotely.
41 Answers
41
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How do I vertically align text in a div?
...the most effective way to align text with a div. I have tried a few things and none seem to work.
30 Answers
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Approximate cost to access various caches and main memory?
Can anyone give me the approximate time (in nanoseconds) to access L1, L2 and L3 caches, as well as main memory on Intel i7 processors?
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Set cellpadding and cellspacing in CSS?
In an HTML table, the cellpadding and cellspacing can be set like this:
28 Answers
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