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Why #define TRUE (1==1) in a C boolean macro instead of simply as 1?

...e TRUE and FALSE according to its own rules, you're making their meanings explicit to programmers, and you're guaranteeing consistency within your program and any other library (assuming the other library follows C standards ... you'd be amazed). Some History Some BASICs defined FALSE as 0 and TR...
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What is the purpose of Flask's context stacks?

I've been using the request/application context for some time without fully understanding how it works or why it was designed the way it was. What is the purpose of the "stack" when it comes to the request or application context? Are these two separate stacks, or are they both part of one stack? Is ...
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Nokogiri installation fails -libxml2 is missing

... First, install the dependencies: sudo apt-get install libxslt-dev libxml2-dev If you still receive the error, you may be missing a compiler toolchain: sudo apt-get install build-essential You'll get the "libxml2 is missing" error if you're missing a build toolchain (at least I...
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How to make the python interpreter correctly handle non-ASCII characters in string operations?

...ions: The source file must be saved using the correct encoding in your text editor as well. In Python 2, the unicode literal must have a u before it, as in s.replace(u"Â ", u"") But in Python 3, just use quotes. In Python 2, you can from __future__ import unicode_literals to obtain the Python 3 b...
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Best way to give a variable a default value (simulate Perl ||, ||= )

...tly from the conditional operator, as it is specific to a null value. For example, if $_GET['name'] is set to an empty string, the first line would return an empty string, but we could return "john doe" by using $_GET['name'] ? $_GET['name'] : 'john doe'. – VPhantom ...
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A route named “x” is already in the route collection. Route names must be unique. Exception with ASP

I'm doing an ASP.NET MVC 3 web service and I keep getting this exception intermittently. 14 Answers ...
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Executing multi-line statements in the one-line command-line?

I'm using Python with -c to execute a one-liner loop, i.e.: 17 Answers 17 ...
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Is there a way to detect if a browser window is not currently active?

...ilitychange", onchange); Current browser support: Chrome 13+ Internet Explorer 10+ Firefox 10+ Opera 12.10+ [read notes] The following code falls back to the less reliable blur/focus method in incompatible browsers: (function() { var hidden = "hidden"; // Standards: if (hidden in docum...
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Iterate a list with indexes in Python

... of for i in range(len(name_of_list)): which is what led me to provide an example using a for instead of what was shown in the first part. – Vinko Vrsalovic Sep 27 '12 at 9:29 1 ...
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Python's “in” set operator

... Yes, but it also means hash(b) == hash(x), so equality of the items isn't enough to make them the same. share | improve this answer | foll...