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Why is Scala's immutable Set not covariant in its type?
...ameter of type A due to the contravariance of functions. Set could potentially be contravariant in A, but this too causes issues when you want to do things like this:
def elements: Iterable[A]
In short, the best solution is to keep things invariant, even for the immutable data structure. You'll...
LINQ: Distinct values
...
Oh so by "larger type" you may mean I still want all properties in the result even though I only want to compare a few properties to determine distinctness?
– The Red Pea
Sep 20 '16 at 14:31
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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...
How to make ng-repeat filter out duplicate results
...sion of ui utils, you can just include ui.unique on its own. use bower install just for the module.
– Learning stats by example
Feb 11 '15 at 19:59
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Python argparse: default value or specified value
...
import argparse
parser = argparse.ArgumentParser()
parser.add_argument('--example', nargs='?', const=1, type=int)
args = parser.parse_args()
print(args)
% test.py
Namespace(example=None)
% test.py --example
Namespace(example=1)
% test.py --example 2
Namespace(example=2)
nargs...
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...
What's the difference between %s and %d in Python string formatting?
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what do you call these %s, %d, etc?
– Chaine
May 19 '17 at 18:21
1
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Global access to Rake DSL methods is deprecated
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You can "delete" Rake 0.9.1 by running the following command:
gem uninstall rake -v=0.9.1
If you have multiple versions of the gem installed, you'll be prompted to pick a version.
After 0.9.1 was cleaned out, I ran
bundle update rake
and was finally able to create my database files. I was ...
How can I get a java.io.InputStream from a java.lang.String?
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You might be right. I originally made it a comment probably because it wasn't an actual answer to OP's question.
– Andres Riofrio
Jul 15 '13 at 18:52
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Completion handler for UINavigationController “pushViewController:animated”?
...rface UINavigationController (CompletionHandler)
- (void)completionhandler_pushViewController:(UIViewController *)viewController
animated:(BOOL)animated
completion:(void (^)(void))completion;
@end
Implementation:
#import "UIN...