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Are Swift variables atomic?
... you, i.e.:
class Car {
static let sharedCar: Car = Car() // will be called inside of dispatch_once
}
private let sharedCar: Car2 = Car2() // same here
class Car2 {
}
Update 05/25/16: Keep an eye out for swift evolution proposal https://github.com/apple/swift-evolution/blob/master/proposals...
Zero-based month numbering [closed]
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The use of zero to start counting is actually an optimization trick from Assembly programmers. Instead of assigning 1 to the count register, they XOR'ed the register with itself, which was slightly faster in CPU cycles. This meant that counting would start with 0 an...
Create or write/append in text file
...
Try something like this:
$txt = "user id date";
$myfile = file_put_contents('logs.txt', $txt.PHP_EOL , FILE_APPEND | LOCK_EX);
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fol...
How do I run a Ruby file in a Rails environment?
...------
#!/usr/bin/env /Users/me/rails_project/script/rails runner
Product.all.each { |p| p.price *= 2 ; p.save! }
-------------------------------------------------------------
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PHP server on local machine?
...d I'm wanting to test my PHP files without uploading them to my host. Basically testing them on my own machine before I upload them. How do I do that?
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class method generates “TypeError: … got multiple values for keyword argument …”
...de:
myfoo.foodo("something")
print
print myfoo
You'll output like:
<__main__.foo object at 0x321c290>
a thong is something
<__main__.foo object at 0x321c290>
You can see that 'thing' has been assigned a reference to the instance 'myfoo' of the class 'foo'. This section of the docs...
Dealing with “java.lang.OutOfMemoryError: PermGen space” error
...rvice.
If you get an error the specified service does not exist as an installed service you should run:
tomcat6w //ES//servicename
where servicename is the name of the server as viewed in services.msc
Source: orx's comment on Eric's Agile Answers.
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What is the purpose of Rank2Types?
I am not really proficient in Haskell, so this might be a very easy question.
6 Answers
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setTimeout / clearTimeout problems
...nswered Jul 31 '17 at 21:45
zero_coolzero_cool
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How do I clone a Django model instance object and save it to the database?
...imary key of your object and run save().
obj = Foo.objects.get(pk=<some_existing_pk>)
obj.pk = None
obj.save()
If you want auto-generated key, set the new key to None.
More on UPDATE/INSERT here.
Official docs on copying model instances: https://docs.djangoproject.com/en/2.2/topics/db/que...