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Does every Javascript function have to return a value?
...ow level, the return is translated into some sort of jump. If a function really returned nothing at all, there would be no way of knowing what and when to call the next function, or to call event handlers and the like.
So to recap: No, a JS function needn't return anything as far as your code goes....
MongoDB: How to query for records where field is null or not set?
...ount({sent_at: {$exists: false}})
If its there and null, or not there at all:
db.emails.count({sent_at: null})
Refer here for querying and null
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isset() and empty() - what to use
... check - is variable empty or contains something. To solve this task, I usually do the following.
6 Answers
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Crontab - Run in directory
...t I would like it to execute it from a particular directory so it can find all the files it needs, since the application has a bunch of relative paths.
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What exception classes are in the standard C++ library
...;exception> interface (debatable if you should catch this)
std::bad_alloc <new> failure to allocate storage
std::bad_array_new_length <new> invalid array length
std::bad_cast <typeinfo> execution of an invalid dynamic-cast
std::bad_exception <exception>...
Retina displays, high-res background images
...ges/box-bg@2x.png') no-repeat top left / 200px 200px;
}
However, I personally would not advise using the shorthand form as it is not supported in iOS <= 6 or Android making it unreliable in most situations.
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Format a date using the new date time API
...in JavaScript or DateTime in Perl) are based on the concept of a universal all-purpose unique temporal type (in German there is the poetic expression "eierlegende Wollmilchsau"). In this design there cannot be an unsupported field. But the price is high: Many time problems cannot be adequately handl...
git push to specific branch
...I'm a bit confused, I'm using v2.10, when I type git push it tries to push all tracked branches, contrary to what you said ("the remote of the current branch is the default value").
– Roberto
Feb 22 '17 at 0:00
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Git fast forward VS no fast forward merge
Git merge allow us to perform fast forward and no fast fast forward branch merging. Any ideas when to use fast forward merge and when to use no fast forward merge?
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Checking for NULL pointer in C/C++ [closed]
In a recent code review, a contributor is trying to enforce that all NULL checks on pointers be performed in the following manner:
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