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JavaScript: empty array, [ ] evaluates to true in conditional structures. Why is this?
...tring)
null
undefined
NaN (a special Number value meaning Not-a-Number!)
All other values are truthy, including "0" (zero in quotes), "false" (false in quotes), empty functions, empty arrays, and empty objects.
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javascript check for not null
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while technically this works, a double not (!!) is a programming faux-pas. It is really the equivalent of if(val), which is much clearer to read. I would stick to that (fyi Ujwal, !!val should technically work in C or C++ also) see here f...
What is the purpose of Order By 1 in SQL select statement?
...is only has the sql tag. In Standard SQL only column correlation names are allowed in the OREDER BY clause because, in theory, the table correlation names are out of scope i.e. should be ORDER BY PAYMENT_DATE;. Of course, not all SQL implementations conform to Standards.
– oned...
How can I unit test Arduino code?
I'd like to be able to unit test my Arduino code. Ideally, I would be able to run any tests without having to upload the code to the Arduino. What tools or libraries can help me with this?
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How to call getClass() from a static method in Java?
...that must have some static methods. Inside these static methods I need to call the method getClass() to make the following call:
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How to show SQL queries run in the Rails console?
... Perfect, just what I needed. Have any recommendation where to go find small tricks such as these are documented?
– randombits
May 29 '10 at 18:18
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Netbeans: how to change @author
...ou might also want to do a Find and Replace(Ctrl + Shift + H) for changing all the already place @ author tag in the project. As the change above doesn't change the already placed @ author.
– T04435
Oct 12 '15 at 6:25
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How can I check in a Bash script if my local Git repository has changes?
... Hi, that was one of the best answers on a question, you just gave me all information that I needed and that others my need as well :). I'll just need the last one, "something has changed" :) and you were right, I copied it.
– kmindi
Feb 28 '11 at 15:34
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Why are private fields private to the type, not the instance?
...this);
}
}
Can the compiler necessarily figure out that other is actually this? Not in all cases. One could argue that this just shouldn't compile then, but that means we have a code path where a private instance member of the correct instance isn't accessible, which I think is even worse.
On...
GridView VS GridLayout in Android Apps
... visible on screen. Whereas if you use a GridLayout you would have to load all the images that will be displayed at anytime causing an outofmemory error in most of devices.
– BigBen3216
Jun 6 '13 at 23:43
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