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What is the difference between NULL, '\0' and 0?
...implicitly checks "is not 0", so we reverse that to mean "is 0".
The following are INVALID ways to check for a null pointer:
int mynull = 0;
<some code>
if (pointer == mynull)
To the compiler this is not a check for a null pointer, but an equality check on two variables. This might work if...
How does the Java 'for each' loop work?
...element of the `fruits` array.
}
So, overall summary:
[nsayer] The following is the longer form of what is happening:
for(Iterator<String> i = someList.iterator(); i.hasNext(); ) {
String item = i.next();
System.out.println(item);
}
Note that if you need to use
i.remove(); in ...
Escape double quotes in parameter
... Ha! I never would have guessed it was wscript's fault! Leave it to Windows :)
– Bryan Field
Oct 13 '11 at 21:41
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Can dplyr package be used for conditional mutating?
...adability for myself and others, but in this case it seems like data.table wins.
– Paul McMurdie
Feb 7 at 19:50
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OpenCV C++/Obj-C: Detecting a sheet of paper / Square Detection
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OpenCV is pretty much the same for all platforms (Win/Linux/Mac/iPhone/...). The difference is that some don't supported the GPU module of OpenCV. Have you built OpenCV for iOS already? Were you able to test it? I think these are the questions you need to answer before tryin...
Are there disadvantages to using a generic varchar(255) for all text-based fields?
...thus in temp tables or sorted results.
I have helped MySQL users who unknowingly created 1.5GB temp tables frequently and filled up their disk space. They had lots of VARCHAR(255) columns that in practice stored very short strings.
It's best to define the column based on the type of data that you...
Compiled vs. Interpreted Languages
... called (which may be many, many times...). So over time, the JIT compiler wins by a long margin.
– mikera
Sep 17 '13 at 13:47
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Why should I prefer single 'await Task.WhenAll' over multiple awaits?
...zation switch and threadpool shuffle. There could be a significant overall win with WhenAll() in that kind of scenario, so... it really depends.
– Chris Moschini
Jan 29 '15 at 23:00
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What does O(log n) mean exactly?
...t's versatile as an example. Plus I got to use robots in my explanation! A win all-around. (Also, it looks like your answer was made before I was even a member on StackOverflow to begin with!)
– John Feminella
Feb 23 '10 at 0:40
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Retrieving the last record in each group - MySQL
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MySQL 8.0 now supports windowing functions, like almost all popular SQL implementations. With this standard syntax, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id...