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What is monkey patching?
...nstance, consider a class that has a method get_data. This method does an external lookup (on a database or web API, for example), and various other methods in the class call it. However, in a unit test, you don't want to depend on the external data source - so you dynamically replace the get_data m...
DISTINCT for only one column
...
FROM Products
) a
WHERE rn = 1
EDIT:
Example using a where clause:
SELECT *
FROM (
SELECT ID,
Email,
ProductName,
ProductModel,
ROW_NUMBER() OVE...
Will console.log reduce JavaScript execution performance?
Will use of the debugging feature console.log reduce JavaScript execution performance? Will it affect the speed of script execution in production environments?
...
How do I get the width and height of a HTML5 canvas?
...
It might be worth looking at a tutorial: Firefox Canvas Tutorial
You can get the width and height of a canvas element simply by accessing those properties of the element. For example:
var canvas = document.getElementById('mycanvas');
var width = canvas.width;
var heigh...
Window vs Page vs UserControl for WPF navigation?
...a page inside your Window. It is mostly used for web-based systems like an XBAP, where you have a single browser window and different pages can be hosted in that window. It can also be used in Navigation Applications like sellmeadog said.
A UserControl is a reusable user-created control that you ca...
Why is semicolon allowed in this python snippet?
...
It seems useful for exec statements e.g. exec('for a in [1,2,3]:print a;print a+1')
– Phil C
Jun 30 '13 at 8:28
...
What's the u prefix in a Python string?
...
You're right, see 3.1.3. Unicode Strings.
It's been the syntax since Python 2.0.
Python 3 made them redundant, as the default string type is Unicode. Versions 3.0 through 3.2 removed them, but they were re-added in 3.3+ for compatibility with Python 2 to aide the 2 to 3 transition.
...
Checking for NULL pointer in C/C++ [closed]
...
In my experience, tests of the form if (ptr) or if (!ptr) are preferred. They do not depend on the definition of the symbol NULL. They do not expose the opportunity for the accidental assignment. And they are clear and succinct.
E...
AngularJS performs an OPTIONS HTTP request for a cross-origin resource
...hich delivers my template files is on a different domain and therefore the XHR request that angular performs must be cross-domain. I've added the appropriate CORS header to my server for the HTTP request to make this work, but it doesn't seem to work. The problem is that when I inspect the HTTP requ...
Error installing mysql2: Failed to build gem native extension
...d other distributions using yum:
sudo yum install mysql-devel
On Mac OS X with Homebrew:
brew install mysql
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