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How can I use if/else in a dictionary comprehension?
...ntioning that you don't need to have an if-else condition for both the key and the value. For example, {(a if condition else b): value for key, value in dict.items()} will work.
– Jeremy Weirich
Jul 26 '16 at 19:41
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ViewDidAppear is not called when opening app from background
I have a View Controller in which my value is 0 (label) and when I open that View Controller from another ViewController I have set viewDidAppear to set value 20 on label. It works fine but when I close my app and than again I open my app but the value doesn't change because viewDidLoad , vie...
Named routes _path vs _url
...st of the time.
_url helpers provide an absolute path, including protocol and server name. I've found that I mainly use these in emails when creating links to the app on the server. They should mainly be used when providing links for external use. (Think email links, RSS, and things like the copy a...
Generating random strings with T-SQL
If you wanted to generate a pseudorandom alphanumeric string using T-SQL, how would you do it? How would you exclude characters like dollar signs, dashes, and slashes from it?
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Can Json.NET serialize / deserialize to / from a stream?
I have heard that Json.NET is faster than DataContractJsonSerializer, and wanted to give it a try...
5 Answers
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Passing a method as a parameter in Ruby
...ult argument in a block declaration like that. So you need to use a splat and setup the default in the proc code itself.
Or, depending on your scope of all this, it may be easier to pass in a method name instead.
def weightedknn(data, vec1, k = 5, weightf = :gaussian)
...
weight = self.send...
Capture keyboardinterrupt in Python without try-except
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Yes, you can install an interrupt handler using the module signal, and wait forever using a threading.Event:
import signal
import sys
import time
import threading
def signal_handler(signal, frame):
print('You pressed Ctrl+C!')
sys.exit(0)
signal.sig...
Postgresql - change the size of a varchar column to lower length
I have a question about the ALTER TABLE command on a really large table (almost 30 millions rows).
One of its columns is a varchar(255) and I would like to resize it to a varchar(40) .
Basically, I would like to change my column by running the following command:
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Is there a pattern for initializing objects created via a DI container
I am trying to get Unity to manage the creation of my objects and I want to have some initialization parameters that are not known until run-time:
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How do I filter an array with AngularJS and use a property of the filtered object as the ng-model at
If I have an array of objects, and I want to bind the Angular model to a property of one of the elements based on a filter, how do I do that? I can explain better with a concrete example:
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