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SQL Add foreign key to existing column
...sed an error trying to create the relationships to the other table. Thanks all.
– ExceptionLimeCat
Apr 30 '12 at 20:35
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How to hide keyboard in swift on pressing return key?
...wDidLoad()
// Do any additional setup after loading the view, typically from a nib.
self.myTextField.delegate = self
}
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
self.view.endEditing(true)
return false
}
}
Code source: http://www...
PHP: exceptions vs errors?
...
Exceptions are thrown - they are intended to be caught. Errors are generally unrecoverable. Lets say for instance - you have a block of code that will insert a row into a database. It is possible that this call fails (duplicate ID) - you will want to have a "Error" which in this case is an "Exc...
Generic type conversion FROM string
...es" for another class. These properties simply have a name and a value. Ideally, what I would like is to be able to add typed properties, so that the "value" returned is always of the type that I want it to be.
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Swift Programming: getter/setter in stored property
...the new value that you assign will replace the one that was just set.
So all you have to do is this:
var rank: Int = 0 {
didSet {
// Say 1000 is not good for you and 999 is the maximum you want to be stored there
if rank >= 1000 {
rank = 999
}
}
}
...
What's the difference between the atomic and nonatomic attributes?
...o are identical; "atomic" is the default behavior (note that it is not actually a keyword; it is specified only by the absence of nonatomic -- atomic was added as a keyword in recent versions of llvm/clang).
Assuming that you are @synthesizing the method implementations, atomic vs. non-atomic chang...
Entity Framework: One Database, Multiple DbContexts. Is this a bad idea? [closed]
...y single context in your application can do that. The trick for this is usually one additional context containing all your entities which is used only for database creation. Your real application contexts containing only subsets of your entities must have database initializer set to null.
There are...
Why can't I use a list as a dict key in python?
..., with the hash as, say, their memory location?
It can be done without really breaking any of the requirements, but it leads to unexpected behavior. Lists are generally treated as if their value was derived from their content's values, for instance when checking (in-)equality. Many would - underst...
How can I add new keys to a dictionary?
...ted to strings). dict.update can also take another dictionary, but I personally prefer not to explicitly create a new dictionary in order to update another one.
– bgusach
Feb 13 '19 at 8:38
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Why do you need explicitly have the “self” argument in a Python method?
... to make things like this explicit rather than based on a rule.
Additionally, since nothing is implied or assumed, parts of the implementation are exposed. self.__class__, self.__dict__ and other "internal" structures are available in an obvious way.
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