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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 explain dependency injection to a 5-year-old? [closed]
...r objects. You may have a database connection, for example, or some other service that you use. These other objects (or services) are dependencies. The simplest way to write the code is simply to create and use those other objects. But this means your object has an inflexible relationship to tho...
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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When is assembly faster than C?
...hat although that's not entirely false, the cases where assembler can actually be used to generate more performant code are both extremely rare and require expert knowledge of and experience with assembly.
...
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...
Use of *args and **kwargs [duplicate]
...u're not sure how many arguments might be passed to your function, i.e. it allows you pass an arbitrary number of arguments to your function. For example:
>>> def print_everything(*args):
for count, thing in enumerate(args):
... print( '{0}. {1}'.format(count, thing))
...
...
Add EBS to Ubuntu EC2 Instance
...ume
step 3: run sudo resize 2fs -p /dev/xvde
step 4: restart apache2 sudo service apache2 restart
step 4: run df -h
You can see total volume attached to your instance.
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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 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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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...