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Do browsers parse javascript on every page load?
...een able to dig up. It's worth noting first that although JavaScript is usually considered to be interpreted and run on a VM, this isn't really the case with the modern interpreters, which tend to compile the source directly into machine code (with the exception of IE).
Chrome : V8 Engine
V8 has...
Select distinct values from a table field
...ant any ordering to be applied to a query, not even the default ordering, call order_by() with no parameters.
and distinct() in the note where it discusses issues with using distinct() with ordering.
To query your DB, you just have to call:
models.Shop.objects.order_by().values('city').distinct(...
Show Youtube video source into HTML5 video tag?
...controls="controls"
class="video-stream"
x-webkit-airplay="allow"
data-youtube-id="N9oxmRT2YWw"
src="http://v20.lscache8.c.youtube.com/videoplayback?sparams=id%2Cexpire%2Cip%2Cipbits%2Citag%2Cratebypass%2Coc%3AU0hPRVRMVV9FSkNOOV9MRllD&itag=43&ipbits=0&...
Pointer to class data member “::*”
...ed in pluggable architectures, but once again producing an example in a small space defeats me. The following is my best (untested) try - an Apply function that would do some pre &post processing before applying a user-selected member function to an object:
void Apply( SomeClass * c, void (Som...
Convert Rows to columns using 'Pivot' in SQL Server
...n but it is easier to see the correct code using a hard-coded version initially.
First up, here are some quick table definitions and data for use:
CREATE TABLE #yt
(
[Store] int,
[Week] int,
[xCount] int
);
INSERT INTO #yt
(
[Store],
[Week], [xCount]
)
VALUES
(102, 1, 96),
(...
How to not run an example using roxygen2?
...answer instead of dontrun. From ?example 'donttest encloses code that typically should be run, but not during package checking.' whereas 'dontrun encloses code that should not be run.' I also got a comment by cran maintainers to switch from dontrun to donttest.
– Julian Karch
...
Android update activity UI from service
I have a service which is checking for new task all the time. If there is new task, I want to refresh the activity UI to show that info.
I did find https://github.com/commonsguy/cw-andtutorials/tree/master/18-LocalService/ this example. Is that a good approch ? Any other examples?
...
in iPhone App How to detect the screen resolution of the device
...l give you the entire screen's resolution in points, so it would most typically be 320x480 for iPhones. Even though the iPhone4 has a much larger screen size iOS still gives back 320x480 instead of 640x960. This is mostly because of older applications breaking.
CGFloat screenScale = [[UIScreen main...
How does Task become an int?
...t; (for a logical result of type T in an async manner)
The compiler does all the appropriate wrapping. The point is that you're asynchronously returning urlContents.Length - you can't make the method just return int, as the actual method will return when it hits the first await expression which ha...
Vertically align an image inside a div with responsive height
...
Here is a technique to align inline elements inside a parent, horizontally and vertically at the same time:
Vertical Alignment
1) In this approach, we create an inline-block (pseudo-)element as the first (or last) child of the parent, and set its height property to 100% to take all the height...