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Should switch statements always contain a default clause?
...pe! based on the language,
// there should probably be some error-handling
// here, maybe an exception
}
2. To handle 'default' actions, where the cases are for special behavior.
You see this a LOT in menu-driven programs and bash shell scripts. You might also see this when a vari...
The differences between .build, .create, and .create! and when should they be used?
So I've been seeing people using .build , .create , and .create! within their controllers more and more lately. What's the difference from just using .new and passing the param'd object and then .save ? Are there pros and cons? Does using these other methods offer benefits?
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virtualenv --no-site-packages and pip still finding global packages?
...on that virtualenv --no-site-packages would create a completely separate and isolated Python environment, but it doesn't seem to.
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Hidden features of Ruby
...actually wrote an gem at one point to do this, but my code was (a) a mess, and (b) slow. I'm very glad that the functionality has made it into core.
– James A. Rosen
Dec 14 '09 at 13:47
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Uploading both data and files in one form using Ajax?
I'm using jQuery and Ajax for my forms to submit data and files but I'm not sure how to send both data and files in one form?
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Error: allowDefinition='MachineToApplication' beyond application level
...he most recent build I had was Debug. I opened the solution, did a bug fix and attempted to build in RRelease mode. Cleaning in Release didn't work but cleaning in Debug did. (Probably a combo of the 2 was what was needed, i.e. clear out any old refs to dlls, whether Debug or Release).
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Getting key with maximum value in dictionary?
...b':3000, 'c': 100}
max(stats.iteritems(), key=operator.itemgetter(1))[0]
And instead of building a new list in memory use stats.iteritems(). The key parameter to the max() function is a function that computes a key that is used to determine how to rank items.
Please note that if you were to have ...
Find a pair of elements from an array whose sum equals a given number
Given array of n integers and given a number X, find all the unique pairs of elements (a,b), whose summation is equal to X.
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How can I prevent the backspace key from navigating back?
On IE I can do this with the (terribly non-standard, but working) jQuery
33 Answers
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SQL “select where not in subquery” returns no results
...emantically the same.
When it is nullable, NOT IN is different, since IN (and, therefore, NOT IN) return NULL when a value does not match anything in a list containing a NULL.
This may be confusing but may become more obvious if we recall the alternate syntax for this:
common_id = ANY
(
SELECT c...