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How to test if list element exists?
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This is actually a bit trickier than you'd think. Since a list can actually (with some effort) contain NULL elements, it might not be enough to check is.null(foo$a). A more stringent test might be to check that the name is actually defined in t...
window.onload vs $(document).ready()
...of using the same event.
jQuery $document.ready function event executes a bit earlier than window.onload and is called once the DOM(Document object model) is loaded on your page. It will not wait for the images, frames to get fully load.
Taken from the following article:
how $document.ready() is d...
Firebug says “No Javascript on this page”, even though JavaScript does exist on the page
...es/2016/02/04/… Firefox 50.0.1 will be released on 2016-12-13, so it's a bit of a wait to see if they fix it.
– CJ Dennis
Nov 23 '16 at 23:24
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running Rails console in production
... meant for testing. RailsCasts has some videos on the topic but they are a bit outdated.
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Why is Github asking for username/password when following the instructions on screen and pushing a n
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I had this same issue and wondered why it didn't happen with a bitbucket repo that was cloned with https. Looking into it a bit I found that the config for the BB repo had a URL that included my username. So I manually edited the config for my GH repo like so and voila, no more username...
Naming of ID columns in database tables
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HLGEMHLGEM
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Removing items from a list [duplicate]
... already answered, an list.iterator() is needed. The listIterator can do a bit of navigation too.
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Java's final vs. C++'s const
...ments, but throws an exception if modifications are attempted, making it a bit like const in C++
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What is a word boundary in regex?
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100% correct. Apologies for not just commenting on yours. I hit submit before I saw your answer.
– Brent Writes Code
Aug 24 '09 at 21:05
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SQL JOIN vs IN performance?
...ead is pretty old but still mentioned often. For my personal taste it is a bit incomplete, because there is another way to ask the database with the EXISTS keyword which I found to be faster more often than not.
So if you are only interested in values from table a you can use this query:
SELECT a...