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Best way to detect Mac OS X or Windows computers with JavaScript or jQuery
... is on Mac and the right side when the user is on PC. Now I'm doing it by examining the user agent, but it can be too easily spoofed for reliable OS detection. Is there a surefire way to detect whether the OS on which the browser is running is Mac OS X or Windows? If not, what's better than user age...
Build error: You must add a reference to System.Runtime
...
To implement the fix first expand out the existing web.config compilation section that looks like this by default:
<compilation debug="true" targetFramework="4.5"/>
Once expanded I then added the following new configuration XML as I wa...
DISTINCT for only one column
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FROM Products
) a
WHERE rn = 1
EDIT:
Example using a where clause:
SELECT *
FROM (
SELECT ID,
Email,
ProductName,
ProductModel,
ROW_NUMBER() OVE...
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...
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?
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How do I get the width and height of a HTML5 canvas?
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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...
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.
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Why is semicolon allowed in this python snippet?
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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
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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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Checking for NULL pointer in C/C++ [closed]
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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...