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Is null reference possible?

... References are not pointers. 8.3.2/1: A reference shall be initialized to refer to a valid object or function. [Note: in particular, a null reference cannot exist in a well-defined program, because the only way to create such a reference would be to bind it to the ...
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Foreign keys in mongo?

...his: class Student include Mongoid::Document field :name embeds_many :addresses embeds_many :scores end class Address include Mongoid::Document field :address field :city field :state field :postalCode embedded_in :student end class Score include Mongoi...
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Django's SuspiciousOperation Invalid HTTP_HOST header

... If your ALLOWED_HOSTS is set correctly, then it is possible someone is probing your site for the vulnerability by spoofing the header. There is discussion right now by the Django developers to change this from a 500 internal server...
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How to access route, post, get etc. parameters in Zend Framework 2

...gt;fromFiles('paramname'); // From file being uploaded   Default values All of these methods also support default values that will be returned if no parameter with the given name is found. Example: $orderBy = $this->params()->fromQuery('orderby', 'name'); When visiting http://example.com/?...
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How does lucene index documents?

...links . But i heard that Lucene project has a special stemmer named "Snowball"? Do you heard anything about that ? – M.Amrollahi Apr 9 '10 at 17:44 ...
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Defining a function with multiple implicit arguments in Scala

... They must all go in one parameter list, and this list must be the last one. def myfun(arg:String)(implicit p1: String, p2:Int)={} share | ...
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Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?

...an work around it from within psql by executing the DDL statement conditionally: SELECT 'CREATE DATABASE mydb' WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'mydb')\gexec The manual: \gexec Sends the current query buffer to the server, then treats each column of each row of the query's...
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Matplotlib: “Unknown projection '3d'” error

...e you using? (Try running: python -c 'import matplotlib; print matplotlib."__version__") I'm guessing you're running version 0.99, in which case you'll need to either use a slightly different syntax or update to a more recent version of matplotlib. If you're running version 0.99, try doing this in...
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How to get one value at a time from a generator function in Python?

... In Python <= 2.5, use gen.next(). This will work for all Python 2.x versions, but not Python 3.x In Python >= 2.6, use next(gen). This is a built in function, and is clearer. It will also work in Python 3. Both of these end up calling a specially named function, next(), wh...
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Automapper - how to map to constructor parameters instead of property setters

... Use ConstructUsing this will allow you to specify which constructor to use during the mapping. but then all of the other properties will be automatically mapped according to the conventions. Also note that this is different from ConvertUsing in that con...