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How do I check if an object has a specific property in JavaScript?
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I'm really confused by the answers that have been given - most of them are just outright incorrect. Of course you can have object properties that have undefined, null, or false values. So simply reducing the property check to typeo...
How do I copy a file in Python?
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Note that not all metadata will be copied, depending on your platform.
– Kevin Horn
Oct 19 '09 at 20:50
14
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Why does MYSQL higher LIMIT offset slow the query down?
...e improvement. If there is no index usable by ORDER BY or the index covers all fields you need, you don't need this workaround.
– Quassnoi
Nov 24 '11 at 18:13
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What is the difference between AF_INET and PF_INET in socket programming?
... to do is to use AF_INET in your
struct sockaddr_in and PF_INET in your call to socket(). But
practically speaking, you can use AF_INET everywhere. And, since
that's what W. Richard Stevens does in his book, that's what I'll do
here.
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Co-variant array conversion from x to y may cause run-time exception
...js[0] = new Foo(); // again legal, with runtime exception
In C#, you are allowed to reference an array of objects (in your case, LinkLabels) as an array of a base type (in this case, as an array of Controls). It is also compile time legal to assign another object that is a Control to the array. Th...
PDO closing connection
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close the connection, you need to destroy the object by ensuring that
all remaining references to it are deleted--you do this by assigning
NULL to the variable that holds the object. If you don't do this
explicitly, PHP will automatically close the connection when your
script ends.
Note...
How to convert a String to CharSequence?
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This answers both. Poster first trivially resolves the String -> CharSequence problem by explaining that a String IS a CharSequence. Then poster answers how to go from CharSequence to String.
– Alex A.
Nov 8 '13 at 23:05...
Iterate an iterator by chunks (of n) in Python? [duplicate]
...y_list[i:i + chunk_size] for i in range(0, len(my_list), chunk_size)]
Finally, a solution that works on general iterators an behaves as desired is
def grouper(n, iterable):
it = iter(iterable)
while True:
chunk = tuple(itertools.islice(it, n))
if not chunk:
return...
How do I get a list of column names from a psycopg2 cursor?
... to generate column labels directly from the selected column names, and recall seeing that python's psycopg2 module supports this feature.
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Globally catch exceptions in a WPF application?
...ication where parts of it may throw exceptions at runtime. I'd like to globally catch any unhandled exception and log them, but otherwise continue program execution as if nothing happened (kinda like VB's On Error Resume Next ).
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