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How to determine if a record is just created or updated in after_save
The #new_record? function determines if a record has been saved. But it is always false in the after_save hook. Is there a way to determine whether the record is a newly created record or an old one from update?
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Why is @autoreleasepool still needed with ARC?
... need to think about memory management at all with Objective-C objects. It is not permitted to create NSAutoreleasePool s anymore, however there is a new syntax:
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Does Python's time.time() return the local or UTC timestamp?
... the number of seconds since the epoch, as seconds. Note that the "epoch" is defined as the start of January 1st, 1970 in UTC. So the epoch is defined in terms of UTC and establishes a global moment in time. No matter where you are "seconds past epoch" (time.time()) returns the same value at the ...
Check if a variable is of function type
Suppose I have any variable, which is defined as follows:
18 Answers
18
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What is the difference between Amazon S3 and Amazon EC2 instance?
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An EC2 instance is like a remote computer running Windows or Linux and on which you can install whatever software you want, including a Web server running PHP code and a database server.
Amazon S3 is just a storage service, typically used t...
What is the best workaround for the WCF client `using` block issue?
...ck as it's pretty much the standard way to use resources that implement IDisposable :
26 Answers
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What are dictionary view objects?
...ply like a window on the keys and values (or items) of a dictionary. Here is an excerpt from the official documentation for Python 3:
>>> dishes = {'eggs': 2, 'sausage': 1, 'bacon': 1, 'spam': 500}
>>> keys = dishes.keys()
>>> values = dishes.values()
>>> # vi...
How to train an artificial neural network to play Diablo 2 using visual input?
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I can see that you are worried about how to train the ANN, but this project hides a complexity that you might not be aware of. Object/character recognition on computer games through image processing it's a highly challenging task (not say crazy for FPS and RPG games). I don't doubt of your...
A simple scenario using wait() and notify() in java
Can I get a complete simple scenario i.e. tutorial that suggest how this should be used, specifically with a Queue?
6 Answe...
Returning a boolean from a Bash function
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Use 0 for true and 1 for false.
Sample:
#!/bin/bash
isdirectory() {
if [ -d "$1" ]
then
# 0 = true
return 0
else
# 1 = false
return 1
fi
}
if isdirectory $1; then echo "is directory"; else echo "nopes"; fi
Edit
From @amichair's comment, these are ...