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Removing multiple keys from a dictionary safely
I know how to remove an entry, 'key' from my dictionary d , safely. You do:
14 Answers
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Purge or recreate a Ruby on Rails database
...or Tracks GTD app db:migrate didn't work. I had to do db:reset when moving from Sqlite3 to Postgres.
– labyrinth
Mar 29 '12 at 4:06
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Error-Handling in Swift-Language
...ay decided to propagate the error, if your are calling a throwing function from a function that is itself marked with throws keyword:
func fulfill(quest: Quest) throws {
let dragon = try summonDefaultDragon()
quest.ride(dragon)
}
Alternatively, you can call throwing function using try?:
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Getting name of the class from an instance
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NSStringFromClass([instance class]) should do the trick.
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Copy files from one directory into an existing directory
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If you want to copy something from one directory into the current directory, do this:
cp dir1/* .
This assumes you're not trying to copy hidden files.
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Does python have an equivalent to Java Class.forName()?
...that holds the class, which required that we first extract the module name from the fully qualified name. Then we import the module:
m = __import__( module )
In this case, m will only refer to the top level module,
For example, if your class lives in foo.baz module, then m will be the module fo...
ReactJS state vs prop
...allbacks down to the children that need to modify your data, and call them from the child component.
Modifying this.props or this.state directly is not a good idea, because React will not be able to pick up on the changes. That's because React does a shallow comparison of your post prop to determin...
How to create a file in Android?
How to create a file, write data into it and read data from it on Android? If possible provide a code snippet.
4 Answers
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Pythonic way to find maximum value and its index in a list?
...iding external dependencies can be worthwhile in some cases, but an import from the standard library is a non-issue.
– Sven Marnach
Aug 7 '17 at 11:14
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How do I return early from a rake task?
... at the beginning, if one of the checks fails I would like to return early from the rake task, I don't want to execute any of the remaining code.
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