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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...
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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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...
What are the most common naming conventions in C?
...I follow the GTK+ coding convention, which can be summarized as follows:
All macros and constants in caps: MAX_BUFFER_SIZE, TRACKING_ID_PREFIX.
Struct names and typedef's in camelcase: GtkWidget, TrackingOrder.
Functions that operate on structs: classic C style: gtk_widget_show(), tracking_order_p...
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...
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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Most efficient T-SQL way to pad a varchar on the left to a certain length?
...ecause you are dealing with a fixed length).
But as I said you should really avoid doing this in your database.
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Python string class like StringBuilder in C#?
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There is no one-to-one correlation. For a really good article please see Efficient String Concatenation in Python:
Building long strings in the Python
progamming language can sometimes
result in very slow running code. In
this article I investigate the
comp...
How to iterate through two lists in parallel?
...hat advantage that only itertools.izip() had in Python 2 and thus it is usually the way to go.
– Daniel S.
Jun 14 '16 at 17:40
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