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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...
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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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 do you declare an interface in C++?
...virtual method list of your interface by adding a virtual destructor. This allows you to pass pointer ownership to another party without exposing the concrete derived class. The destructor doesn't have to do anything, because the interface doesn't have any concrete members. It might seem contradicto...
How to choose between Hudson and Jenkins? [closed]
... understand why, you need to know the history of the project. It was originally open source and supported by Sun. Like much of what Sun did, it was fairly open, but there was a bit of benign neglect. The source, trackers, website, etc. were hosted by Sun on their relatively closed java.net platform....
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...
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
1
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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...
How to check whether a file is empty or not?
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What is the difference/advantage using this vs os.state('file').st_size?
– Elijah Lynn
Nov 25 '17 at 0:30
3
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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...