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How do I get the collection of Model State Errors in ASP.NET MVC?

... @DaveH Yep, you should totally check for existence first – Alex Lyman Dec 4 '13 at 20:03 add a comment  |  ...
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How can I get file extensions with JavaScript?

... Newer Edit: Lots of things have changed since this question was initially posted - there's a lot of really good information in wallacer's revised answer as well as VisioN's excellent breakdown Edit: Just because this is the accepted answer; wallacer's answer is indeed much better: return f...
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Get list from pandas DataFrame column headers

...input so I won't know how many columns there will be or what they will be called. 19 Answers ...
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Why is Node.js single threaded? [closed]

...rvers every client request is instantiated on a new thread. But in Node.js all the clients run on the same thread (they can even share the same variables!) I understand that I/O operations are event-based so they don't block the main thread loop. ...
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How to return dictionary keys as a list in Python?

...] New unpacking generalizations (PEP 448) were introduced with Python 3.5 allowing you to now easily do: >>> newdict = {1:0, 2:0, 3:0} >>> [*newdict] [1, 2, 3] Unpacking with * works with any object that is iterable and, since dictionaries return their keys when iterated throug...
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Is there a performance impact when calling ToList()?

...on) constructor. This constructor must make a copy of the array (more generally IEnumerable<T>), otherwise future modifications of the original array will change on the source T[] also which wouldn't be desirable generally. I would like to reiterate this will only make a difference with a hu...
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What is the difference between Modal and Push segue in Storyboards?

...visual indication: A modal Segue is just one VC presenting another VC modally. The VCs don't have to be part of a navigation controller and the VC being presented modally is generally considered to be a "child" of the presenting (parent) VC. The modally presented VC is usually sans any navigatio...
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Git push results in “Authentication Failed”

...ettings of your Github account. Using this token as your password should allow you to push to your remote repository via HTTPS. Use your username as usual. https://help.github.com/articles/creating-a-personal-access-token-for-the-command-line/ You may also need to update the origin for your r...
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How to find time complexity of an algorithm

...term is 2 million and the second term is only 2. For this reason, we drop all but the largest terms for large N. So, now we have gone from 2N + 2 to 2N. Traditionally, we are only interested in performance up to constant factors. This means that we don't really care if there is some constant mu...
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Max length for client ip address [duplicate]

...esses are 128 bits (as opposed to 32 bits of IPv4 addresses). They are usually written as 8 groups of 4 hex digits separated by colons: 2001:0db8:85a3:0000:0000:8a2e:0370:7334. 39 characters is appropriate to store IPv6 addresses in this format. Edit: However, there is a caveat, see @Deepak's ans...