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When would I use Task.Yield()?
...equires some "long running" initialization, ie:
private async void button_Click(object sender, EventArgs e)
{
await Task.Yield(); // Make us async right away
var data = ExecuteFooOnUIThread(); // This will run on the UI thread at some point later
await UseDataAsync(data);
}
...
A fast method to round a double to a 32-bit int explained
...
For those who'd like to convert to int64_t you can do that by shifting the mantissa left and then right by 13 bits. This will clear the exponent and the two bits from the 'magic' number, but will keep and propagate the sign to the entire 64-bit signed integer. unio...
What is the standard naming convention for html/css ids and classes?
... while, I've gone back to dashes. To me now they look a lot cleaner than un_der_scores or camelCase. My original point still stands though: there isn't a standard.
Update 2015
An interesting corner case with conventions here is Rust. I really like the language, but the compiler will warn you if yo...
Given final block not properly padded
...here:
http://www.rsa.com/products/bsafe/documentation/cryptoj35html/doc/dev_guide/group_CJ_SYM__PAD.html
(I assume you have the issue when you try to encrypt)
You can choose your padding schema when you instantiate the Cipher object. Supported values depend on the security provider you are using. ...
NSObject +load and +initialize - What do they do?
... can see how the runtime looks up the load method as a special case in the _class_getLoadMethod of objc-runtime-new.mm, and calls it directly from call_class_loads in objc-loadmethod.mm.
The runtime also runs the load method of every category it loads, even if several categories on the same class i...
Waiting until two async blocks are executed before starting another block
...y Programming Guide
Your example could look something like this:
dispatch_group_t group = dispatch_group_create();
dispatch_group_async(group,dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), ^ {
// block1
NSLog(@"Block1");
[NSThread sleepForTimeInterval:5.0];
NSLog(@"Bl...
How do you write a migration to rename an ActiveRecord model and its table in Rails?
...ameOldTableToNewTable < ActiveRecord::Migration
def self.up
rename_table :old_table_name, :new_table_name
end
def self.down
rename_table :new_table_name, :old_table_name
end
end
I had to go and rename the model declaration file manually.
Edit:
In Rails 3.1 & 4, ActiveReco...
The difference between fork(), vfork(), exec() and clone()
...all program (think Java's Runtime.exec()). POSIX has standardized the posix_spawn() to replace these latter two more modern uses of vfork().
posix_spawn() does the equivalent of a fork()/execve(), and also allows some fd juggling in between. It's supposed to replace fork()/execve(), mainly for non-M...
How to resize an image with OpenCV2.0 and Python2.6
...ll resize the image to have 100 cols (width) and 50 rows (height):
resized_image = cv2.resize(image, (100, 50))
Another option is to use scipy module, by using:
small = scipy.misc.imresize(image, 0.5)
There are obviously more options you can read in the documentation of those functions (cv2.r...
64-bit version of Boost for 64-bit windows
... it is also possible to use the stagedir parametter: "bjam --stagedir=./lib_64bit address-model=64 toolset=msvc threading=multi" and "bjam --stagedir=./lib toolset=msvc threading=multi"
– Odin
Jul 11 '12 at 15:20
...