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How to convert a string or integer to binary in Ruby?

... You would naturally use Integer#to_s(2), String#to_i(2) or "%b" in a real program, but, if you're interested in how the translation works, this method calculates the binary representation of a given integer using basic operators: def int_t...
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How to restore to a different database in sql server?

...mpCopy with the contents of your.bak. Example (restores a backup of a db called 'creditline' to 'MyTempCopy'; RESTORE FILELISTONLY FROM DISK='e:\mssql\backup\creditline.bak' >LogicalName >-------------- >CreditLine >CreditLine_log RESTORE DATABASE MyTempCopy FROM DISK='e:\mssql\backu...
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Send and receive messages through NSNotificationCenter in Objective-C?

... @implementation TestClass - (void) dealloc { // If you don't remove yourself as an observer, the Notification Center // will continue to try and send notification objects to the deallocated // object. [[NSNotificationCenter defaultCenter] removeO...
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How to delete migration files in Rails 3

... I usually: Perform a rake db:migrate VERSION=XXX on all environments, to the version before the one I want to delete. Delete the migration file manually. If there are pending migrations (i.e., the migration I removed was not the...
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what is reverse() in Django

...!-- django <= 1.4 --> <a href="{% url url_name %}">link which calls some_view</a> <!-- django >= 1.5 or with {% load url from future %} in your template --> <a href="{% url 'url_name' %}">link which calls some_view</a> This will be rendered as: <a href="...
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How to get a Docker container's IP address from the host

...n. Maybe provide two examples clearly labelled Linux and Windows. I literally just typed the example, checked the docs which also uses single quotes and then Googled the error. I'm sure I'm not alone. – Wyck Apr 15 '19 at 18:42 ...
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How to create a GUID/UUID using iOS

...tring = CFUUIDCreateString(NULL, theUUID); CFRelease(theUUID); return (__bridge NSString *)string; } EDIT: Jan, 29 2014: If you're targeting iOS 6 or later, you can now use the much simpler method: NSString *UUID = [[NSUUID UUID] UUIDString]; ...
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Why do we need message brokers like RabbitMQ over a database like PostgreSQL?

...ustering options are also available. In regards to AMQP, I would say a really cool feature is the "exchange", and the ability for it to route to other exchanges. This gives you more flexibility and enables you to create a wide array of elaborate routing typologies which can come in very handy when...
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find() with nil when there are no records

... Yes, just do: Challenge.find_by_id(10) For Rails 4 and 5: Challenge.find_by(id: 10) share | improve this answer | ...
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Case-insensitive string comparison in C++ [closed]

...case-insensitive string comparison in C++ without transforming a string to all uppercase or all lowercase? 30 Answers ...