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What is the purpose of willSet and didSet in Swift?
... for instance to notify other objects that the property just changed. When all you have is get/set, you need another field to hold the value. With willSet and didSet, you can take action when the value is modified without needing another field. For instance, in that example:
class Foo {
var myP...
How to request Administrator access inside a batch file
...s method doesn't forward arguments. Do you know How that can be done? Basically what I observe is that on the first line %1 has some value and on the last line %1 is null. I need to forward the arguments.
– prongs
Jan 11 '13 at 11:54
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add column to mysql table if it does not exist
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OK this is really crude but someone's got to say it. if you are simply running a SQL script from the command line, you can give mysql the --force switch, which means keep going even if there's an error. then, just go for it. you just want...
How to avoid .pyc files?
... I just tried this and, it does work for imported modules. Specifically, once this variable is set anything imported later won't generate pyc files. This is delightful. Thanks.
– user234736
Nov 22 '12 at 19:59
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Can I use Objective-C blocks as properties?
... @CharlieMonroe - Yes you are probably right, but dont you need a dealloc implementation to nil or release the block property without ARC? (its been a while since I used non-ARC)
– Robert
Mar 31 '13 at 21:58
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How can I get the concatenation of two lists in Python without modifying either one? [duplicate]
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Actually you can do this by using the a non hidden function: import operator, operator.add(list1, list2)
– e-satis
Apr 13 '11 at 12:28
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How to set selected value of jquery select2?
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To dynamically set the "selected" value of a Select2 component:
$('#inputID').select2('data', {id: 100, a_key: 'Lorem Ipsum'});
Where the second parameter is an object with expected values.
UPDATE:
This does work, just wanted to n...
What is the proper way to re-attach detached objects in Hibernate?
...e to the DB,
and overwrite any intervening updates.
refresh() cannot be called on a detached entity.
lock() cannot be called on a detached entity,
and even if it could, and it did reattach the entity,
calling 'lock' with argument 'LockMode.NONE'
implying that you are locking, but not locking,
i...
Will using 'var' affect performance?
...ay have chosen an Interface or parent type if you were to set the type manually.
Update 8 Years Later
I need to update this as my understanding has changed. I now believe it may be possible for var to affect performance in the situation where a method returns an interface, but you would have used a...
Reload django object from database
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Not sure what "All non-deferred fields are updated "mentioned in the docs means?
– Yunti
Nov 13 '15 at 18:15
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