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How do I pass a variable by reference?
...n seems unclear about whether parameters are passed by reference or value, and the following code produces the unchanged value 'Original'
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What's quicker and better to determine if an array key exists in PHP?
... if the value is NULL.
Whereas
isset() will return false if the key exist and value is NULL.
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SQL how to make null values come last when sorting ascending
...e with a datetime field. The field in question can be null. I have a query and I want the results sorted ascendingly by the datetime field, however I want rows where the datetime field is null at the end of the list, not at the beginning.
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What is the difference between __init__ and __call__?
I want to know the difference between __init__ and __call__ methods.
13 Answers
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Elegant way to check for missing packages and install them?
...de with coauthors these days. Many of them are novice/intermediate R users and don't realize that they have to install packages they don't already have.
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Wireshark localhost traffic capture [closed]
...ssible - read below. You can use the local address of your machine instead and then you'll be able to capture stuff. See CaptureSetup/Loopback.
Summary: you can capture on the
loopback interface on Linux, on
various BSDs including Mac OS X, and
on Digital/Tru64 UNIX, and you might
be abl...
Python function attributes - uses and abuses [closed]
Not many are aware of this feature, but Python's functions (and methods) can have attributes . Behold:
8 Answers
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Apple Mach-O Linker Error when compiling for device
I've just upgraded to xcode 4.0 and I can no longer deploy to iPhone, I get a Apple Mach-O Linker Error, it still works for the simulator though.
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Jdbctemplate query for string: EmptyResultDataAccessException: Incorrect result size: expected 1, ac
...ueryForObject all such methods expects that executed query will return one and only one row. If you get no rows or more than one row that will result in IncorrectResultSizeDataAccessException . Now the correct way is not to catch this exception or EmptyResultDataAccessException, but make sure the qu...
What's the difference of “./configure” option “--build”, “--host” and “--target”?
The script ./configure accepts 3 options --build , --host and --target . I'm confusing their roles. What's the difference and semantics of them?
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