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How to convert Set to String[]?
...'s recommended. Update the answer. "Since late updates of OpenJDK 6 this call was intrinsified, making the performance of the empty array version the same and sometimes even better, compared to the pre-sized version. Also passing pre-sized array is dangerous for a concurrent or synchronized collect...
Uninstall old versions of Ruby gems
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# remove all old versions of the gem
gem cleanup rjb
# choose which ones you want to remove
gem uninstall rjb
# remove version 1.1.9 only
gem uninstall rjb --version 1.1.9
# remove all versions less than 1.3.4
gem uninstall rjb --v...
How to execute a JavaScript function when I have its name as a string
...cript as a string. How do I convert that into a function pointer so I can call it later?
34 Answers
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Partly cherry-picking a commit with Git
...etting you decide whether each hunk should go in, and even letting you manually edit the patch if necessary.
To use it in combination with cherry-pick:
git cherry-pick -n <commit> # get your patch, but don't commit (-n = --no-commit)
git reset # unstage the changes from the...
How important is the order of columns in indexes?
... 3, the optimizer wouldn't even use the index, because it's not helpful at all in narrowing down the result sets. Anytime you're in a query, narrowing down the number of results to deal with before the next step means better performance.
Since the index is also stored this way, there's no backtrac...
When does invoking a member function on a null instance result in undefined behavior?
...) and (b) result in undefined behavior. It's always undefined behavior to call a member function through a null pointer. If the function is static, it's technically undefined as well, but there's some dispute.
The first thing to understand is why it's undefined behavior to dereference a null poin...
Difference between $(window).load() and $(document).ready() functions
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document.ready is a jQuery event, it runs when the DOM is ready, e.g. all elements are there to be found/used, but not necessarily all content.
window.onload fires later (or at the same time in the worst/failing cases) when images and such are loaded, so if you're using image dimensions for exa...
Sum a list of numbers in Python
...does integer division: it discards the remainder. To divide things through all the way, we need to use floating-point numbers. Fortunately, dividing an int by a float will produce a float, so we just use 2.0 for our divisor instead of 2.
Thus:
averages = [(x + y) / 2.0 for (x, y) in zip(my_list[:-...
How can I scroll a web page using selenium webdriver in python?
...selenium webdriver to parse through facebook user friends page and extract all ids from the AJAX script. But I need to scroll down to get all the friends. How can I scroll down in Selenium. I am using python.
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Unable to run app in Simulator: Xcode beta 6 iOS 8
...; Manage Devices
Click on the little + sign at the bottom
Add (if missing) all the devices that you want, or delete and recreate the ones malfunctioning.
If anyone of the simulator is not working then right click on it and delete it and then re-create it again
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