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What's the difference between returning void and returning a Task?
... at various C# Async CTP samples I see some async functions that return void , and others that return the non-generic Task . I can see why returning a Task<MyType> is useful to return data to the caller when the async operation completes, but the functions that I've seen that have a retur...
What's the difference between ContentControl and ContentPresenter?
...ave a Content-property (for example, Button).
ContentPresenter is used inside control templates to display content.
ContentControl, when used directly (it's supposed to be used as a base class), has a control template that uses ContentPresenter to display it's content.
My rules of thumb (not appl...
git rebase without changing commit timestamps
...
Update June 2014: David Fraser mentions in the comments a solution also detailed in "Change timestamps while rebasing git branch", using the option --committer-date-is-author-date (introduced initially in Jan. 2009 in commit 3f01ad6
Note that th...
Drawing an SVG file on a HTML5 canvas
...ssets/images/logo.svg as the first available SVG I found. Worked in FF. jsfiddle.net/Na6X5/331
– Thomas
Mar 10 '15 at 4:24
1
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Change a column type from Date to DateTime during ROR migration
... This answer is only partially correct, you can not use change_column inside change even on rails 4 or down migration will not work. You should use up/down no matter the version of rails.
– Alan Peabody
Jul 18 '14 at 18:31
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Why do we need message brokers like RabbitMQ over a database like PostgreSQL?
...
Rabbit's queues reside in memory and will therefore be much faster than implementing this in a database. A (good)dedicated message queue should also provide essential queueing related features such as throttling/flow control, and the ability to...
Differences between distribute, distutils, setuptools and distutils2?
...ion, and don't trust out-of-date information.
The Python Packaging User Guide is worth a read. Every page has a "last updated" date displayed, so you can check the recency of the manual, and it's quite comprehensive. The fact that it's hosted on a subdomain of python.org of the Python Software Foun...
When splitting an empty string in Python, why does split() return an empty list while split('\n') re
...ode (with an argument such as \n) will produce the first empty field. Consider if you had written '\n'.split('\n'), you would get two fields (one split, gives you two halves).
Question: Is there any specific reason for such a difference?
This first mode is useful when data is aligned in colu...
GUI not working after rewriting to MVC
...r Model needs a way to notify the View of changes. Several approaches are widely used:
In the example below, Model extends Observable for simplicity.
A more common approach uses an EventListenerList, as shown in the Converter application and suggested by the large number of EventListener subinterf...
How to remove all callbacks from a Handler?
...ndler = new Handler();
Runnable myRunnable = new Runnable() {
public void run() {
//Some interesting task
}
};
You can call myHandler.postDelayed(myRunnable, x) to post another callback to the message queue at other places in your code, and remove all pending callbacks with myHandl...