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Is there a CSS parent selector?
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It would seem that it has already been suggested and rejected: stackoverflow.com/questions/45004/…
– RobM
Oct 27 '10 at 12:22
14
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How to compare variables to undefined, if I don’t know whether they exist? [duplicate]
In JavaScript you can declare a variable and if it’s undefined , you can check variable == undefined ; I know that, but how can you compare a value that you don’t know yet if it’s in memory?
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How do I read a text file of about 2 GB? [duplicate]
...the fast, smart log explorer.
I have opened log file of size around 2 GB, and the search is also very fast.
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How do I get the current time zone of MySQL?
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From the manual (section 9.6):
The current values of the global and client-specific time zones can be retrieved like this:
mysql> SELECT @@global.time_zone, @@session.time_zone;
Edit The above returns SYSTEM if MySQL is set to slave to the system's timezone, which is less than help...
How can I create a copy of an object in Python?
... you can use the copy.deepcopy() function.
For more details about shallow and deep copying please refer to the other answers to this question and the nice explanation in this answer to a related question.
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Is there any performance reason to declare method parameters final in Java?
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The final keyword does not appear in the class file for local variables and parameters, thus it cannot impact the runtime performance. It's only use is to clarify the coders intent that the variable not be changed (which many consider dubious reason for its usage), and dealing with anonymous inn...
Get the position of a div/span tag
... the page. Basically you have to loop up through all the element's parents and add their offsets together.
function getPos(el) {
// yay readability
for (var lx=0, ly=0;
el != null;
lx += el.offsetLeft, ly += el.offsetTop, el = el.offsetParent);
return {x: lx,y: ly};
}
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How to get Core Data object from specific Object ID?
...se comment.)
[eta.: Another important difference between the first method and the other two is that existingObjectWithID:error: never returns a fault; it always fetches the whole object for you. If you're trying to avoid that (e.g. working with an expensive-to-fetch object with a big blob property)...
Redis is single-threaded, then how does it do concurrent I/O?
...pends on how you define concurrency.
In server-side software, concurrency and parallelism are often considered as different concepts. In a server, supporting concurrent I/Os means the server is able to serve several clients by executing several flows corresponding to those clients with only one com...
How to execute a Python script from the Django shell?
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Another solution that appears to work for both Python 2.x and 3.x is echo 'import myscript' | python manage.py shell. I've found this can be useful for quick-and-dirty scripts that you only need to run once, without having to go through the cumbersome process of creating a manage.py...