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What is a smart pointer and when should I use one?
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A smart pointer is like a regular (typed) pointer, like "char*", except when the pointer itself goes out of scope then what it points to is deleted as well. You can use it like you would a regular pointer, by using "->", but not if you need an actual pointer to the data. For tha...
What's the main difference between Java SE and Java EE? [duplicate]
...terprise platform technologies.
Java EE is far more than just a couple of extra libraries (that is what I thought when I first looked at it) since there are a ton of frameworks and technologies built upon the Java EE specifications.
But it all boils down to just plain old java.
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SQL : BETWEEN vs =
...>='2009-04-17' and transactiondate<='2009-04-22'
I have to take an extra moment to make sure the two fields are the same.
Also, as a query gets edited over time, a sloppy programmer might separate the two fields. I've seen plenty of queries that say something like
where transactiondate>...
Specifying column name in a “references” migration
...eferences :col_name, references: other_table_name works without installing extra gems.
– Qqwy
Sep 9 '19 at 14:26
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Modifying a subset of rows in a pandas dataframe
...at replacing 0s with an integer instead of np.nan. I wonder what takes the extra time.
– Alexander
Aug 21 '18 at 13:30
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How to break nested loops in JavaScript? [duplicate]
... loops to separate functions, it will run marginally slower because of the extra function calls.
– Tim Down
Oct 14 '09 at 10:39
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trying to align html button at the center of the my page [duplicate]
...ents, you'll have to provide wrapper elements for those. I don't think the extra div is worse than applying custom rules for navigation and other page elements that would otherwise be affected.
– Mohamad
Jul 9 '13 at 15:48
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Traverse a list in reverse order in Python
...d the loop index, and don't want to traverse the entire list twice, or use extra memory, I'd write a generator.
def reverse_enum(L):
for index in reversed(xrange(len(L))):
yield index, L[index]
L = ['foo', 'bar', 'bas']
for index, item in reverse_enum(L):
print index, item
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Look up all descendants of a class in Ruby
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For extra safety one should write ObjectSpace.each_object(::Class) - this will keep the code working when you happen to have a YourModule::Class defined.
– Rene Saarsoo
Oct 3 '11 at 10:42
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What is the >>>= operator in C?
...s a boolean it's true, so 0xFULL ? '\0' : -1 evaluates to '\0', which is a character literal whose numerical value is simply 0.
Meanwhile, 0X.1P1 is a hexadecimal floating point literal equal to 2/16 = 0.125. In any case, being non-zero, it's also true as a boolean, so negating it twice with !! ag...