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Rake just one migration

...n a single migration that changed and needed to be re-run independently of all other migrations. Fire up the console and do this: >> require 'db/migrate/your_migrations.rb' => ["YourMigrations"] >> YourMigrations.up => etc... as the migration runs >> YourMigration.down Mor...
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Xml serialization - Hide null values

...bleInt.HasValue; } Here is a full sample public class Person { public string Name {get;set;} public int? Age {get;set;} public bool ShouldSerializeAge() { return Age.HasValue; } } Serialized with the following code Person thePerson = new Person(){Name="Chris"}; XmlSerializer xs =...
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Ruby convert Object to Hash

... instance_values can be used for all ruby objects for the similar output. – bishal Jan 22 '19 at 11:37 add a comment ...
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How to close tag properly?

...es the tag properly. Best to add the alt attribute for people that are visually impaired. share | improve this answer | follow | ...
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How to check if a line is blank using regex

...like this in multiline mode: ^\s*$ Explanation: ^ is the beginning of string anchor. $ is the end of string anchor. \s is the whitespace character class. * is zero-or-more repetition of. In multiline mode, ^ and $ also match the beginning and end of the line. References: regular-expression...
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Link to “pin it” on pinterest without generating a button

... or hundreds of posts, each one with social buttons. I just can't generate all the buttons for each url: it is too slow (facebook, g+, twitter, pinterest... for hundreds of links). So, instead of the facebook share button to be generated on the fly, I use a simple img pointing to ...
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Python: finding an element in a list [duplicate]

...hod .index. For the objects in the list, you can do something like: def __eq__(self, other): return self.Value == other.Value with any special processing you need. You can also use a for/in statement with enumerate(arr) Example of finding the index of an item that has value > 100. for...
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postgresql - sql - count of `true` values

... You can actually omit ELSE null to get the same result. – 200_success May 12 '16 at 18:26  |...
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Replace one character with another in Bash

I need to be able to do is replace a space ( ) with a dot ( . ) in a string in bash. 6 Answers ...
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How can I reset a react component including all transitively reachable state?

I occasionally have react components that are conceptually stateful which I want to reset. The ideal behavior would be equivalent to removing the old component and readding a new, pristine component. ...