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How to build a query string for a URL in C#?

... select string.Format( "{0}={1}", HttpUtility.UrlEncode(key), HttpUtility.UrlEncode(value)) ).ToArray(); return "?" + string.Join("&", array); } I imagine there's a super elegant way to do this in LINQ too... ...
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Test if string is a number in Ruby on Rails

...is_number? string true if Float(string) rescue false end And then call it like this: my_string = '12.34' is_number?( my_string ) # => true Extend String Class. If you want to be able to call is_number? directly on the string instead of passing it as a param to your helper function, then ...
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How to compare two revisions in Bitbucket?

My team is using Bitbucket for our git repository and we've recently starting using the pull request functionality for code reviews. It works fine on the first review, but if it goes through multiple iterations (that is, changes are made and pull request updated), I would like to see a link with ju...
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Why do we need C Unions?

... and floats: union { int i; float f; } u; // Convert floating-point bits to integer: u.f = 3.14159f; printf("As integer: %08x\n", u.i); Although this is technically undefined behavior according to the C standard (you're only supposed to read the field which was most recently written), it wil...
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How do I calculate the date in JavaScript three months prior to today?

... that one month ago means the same day of the month on the previous month citation needed. But more than half the time, that is 31 days ago, not 30. And if today is the 31st of the month (and it isn't August or Decemeber), that day of the month doesn't exist in the previous month. Interestingly, ...
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Open Cygwin at a specific folder

... When you install Cygwin (or if you’ve already installed it, download it again and start setup again to run an update), make sure that you select the chere package under the "Shells" category. After Cygwin is launched, open up a Cygwin terminal (as an administrator) and type the c...
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Does MySQL ignore null values on unique constraints?

I have an email column that I want to be unique. But I also want it to accept null values. Can my database have 2 null emails that way? ...
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How to learn R as a programming language [closed]

...o learn the R language as as 'programming' language as opposed to learning it as a statistical system. My question is prompted by lack of understanding of such functions as parse, eval, etc. which may not find frequent use by an R user with a 'statistics' persuasion. ...
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Check if a given key already exists in a dictionary

... and if you wanted to always ensure a default value for any key you can either use dict.setdefault() repeatedly or defaultdict from the collections module, like so: from collections import defaultdict d = defaultdict(int) for i in range(100): d[i % 10] += 1 but in general, the in keyword ...
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Are HTTP headers case-sensitive?

... Header names are not case sensitive. From RFC 2616 - "Hypertext Transfer Protocol -- HTTP/1.1", Section 4.2, "Message Headers": Each header field consists of a name followed by a colon (":") and the field value. Field names are case-insensitive. Th...