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Retain cycle on `self` with blocks
...nswered Dec 4 '10 at 8:14
Lily BallardLily Ballard
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What is the benefit of using Fragments in Android, rather than Views?
...tom views are more light weight and simpler to implement.
At first, I actually tried to build a phone/tablet app using custom views. Everything appeared to work across phones AND tablets, even switching from single panel to split panel. Where I ran into trouble was with the back button and life c...
Python list subtraction operation
... [1,2] you will get empty list. [1,1,2,2] - [2] gives [1,1] So it is not really list substraction, it is more like "List from List X without elements from set Y".
– Alfred Zien
Feb 6 '16 at 10:25
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How do I pass values to the constructor on my wcf service?
... How can I use it for self hosting? I receive an exception after calling to CreateServiceHost. I can only call to the protected method public override ServiceHostBase CreateServiceHost(string constructorString, Uri[] baseAddresses); The exception is The exception message was: 'ServiceHostF...
What is the correct way to represent null XML elements?
...l is the correct way to represent a value such that:
When the DOM Level 2 call getElementValue() is issued, the NULL value is returned.
xsi:nil is also used to indicate a valid element with no content even if that elements content type normally doesn't allow empty elements.
If an empty tag is used,...
What are Long-Polling, Websockets, Server-Sent Events (SSE) and Comet?
...s prior to HTML5 which use streaming and long-polling to achieve real time applications. Read more on wikipedia or this article.
Now, which one of them should I use for a realtime app (that I need to
code). I have been hearing a lot about websockets (with socket.io [a
node.js library]) but...
How do you delete an ActiveRecord object?
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It's destroy and destroy_all methods, like
user.destroy
User.find(15).destroy
User.destroy(15)
User.where(age: 20).destroy_all
User.destroy_all(age: 20)
Alternatively you can use delete and delete_all which won't enforce :before_destroy and :after...
How to design a database for User Defined Fields?
...rformance is the primary concern, I would go with #6... a table per UDF (really, this is a variant of #2). This answer is specifically tailored to this situation and the description of the data distribution and access patterns described.
Pros:
Because you indicate that some UDFs
have values for a...
Get a random boolean in python?
... but I found that random.getrandbits(1) to be quite a lot faster. If you really want a boolean instead of a long then
bool(random.getrandbits(1))
is still about twice as fast as random.choice([True, False])
Both solutions need to import random
If utmost speed isn't to priority then random.choic...
Algorithm to detect overlapping periods [duplicate]
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I don't see how this covers all scenarios.
– doker
Sep 24 '14 at 10:55
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