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Core Data: Quickest way to delete all instances of an entity
...ar")
let deleteRequest = NSBatchDeleteRequest(fetchRequest: fetchRequest)
do {
try myPersistentStoreCoordinator.execute(deleteRequest, with: myContext)
} catch let error as NSError {
// TODO: handle the error
}
Objective-C
NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityN...
How to pick just one item from a generator?
...en in my answer, next(g). This will internally call g.__next__(), but you don't really have to worry about that, just as you usually don't care that len(a) internally calls a.__len__().
– Sven Marnach
Apr 10 '14 at 10:31
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In Python, what happens when you import inside of a function? [duplicate]
...
Does it re-import every time the function is run?
No; or rather, Python modules are essentially cached every time they are imported, so importing a second (or third, or fourth...) time doesn't actually force them to go thro...
How to remove selected commit log entries from a Git repository while keeping their changes?
...selected commit log entries from a linear commit tree, so that the entries do not show in the commit log.
9 Answers
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How do you write multiline strings in Go?
Does Go have anything similar to Python's multiline strings:
9 Answers
9
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What are the differences between virtual memory and physical memory?
...lization in operating systems. Considering RAM as the physical memory, why do we need the virtual memory for executing a process?
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How do I detect whether a Python variable is a function?
...u can read the discussion here: http://bugs.python.org/issue10518. You can do this with:
callable(obj)
If this is for Python 3.x but before 3.2, check if the object has a __call__ attribute. You can do this with:
hasattr(obj, '__call__')
The oft-suggested types.FunctionTypes approach is not co...
How do I pass multiple parameters into a function in PowerShell?
... I prefer using the paranthesis and comma separated.. is it possible to do this in powershell?
– sam yi
Mar 19 '14 at 4:27
9
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Add a reference column migration in Rails 4
...s tables and wish to add a new relationship between them.
All you need to do is: just generate a migration using the following command:
rails g migration AddUserToUploads user:references
Which will create a migration file as:
class AddUserToUploads < ActiveRecord::Migration
def change
...
What Xcode keyboard shortcuts do you use regularly? [closed]
What Xcode keyboard shortcuts do you use regularly?
16 Answers
16
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