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Difference between if () { } and if () : endif;
... @alex It will work with curly brackets as well, but at least personally I find this way kind of clearer in things like this. Cause they you know that it is the end of an if, and not the end of a loop of some sort or something else. Think you have endfor and endwhile or something similar too....
How to check the version before installing a package using apt-get?
I'm thinking to install hylafax+ version 5.5.4 which was release last month on my Debian PC.
10 Answers
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What is the difference between const and readonly in C#?
...time of a definition for a const VS readonly values can be computed dynamically but need to be assigned before the constructor exits.. after that it is frozen.
'const's are implicitly static. You use a ClassName.ConstantName notation to access them.
There is a subtle difference. Consider a class d...
Tick symbol in HTML/XHTML
...splay a tick symbol (✓ or ✔) within an internal web app and would ideally like to avoid using an image.
14 Answers
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Difference between window.location.href=window.location.href and window.location.reload()
...
Also note that location.reload() will also force reload all static content (much like a ctrl+f5 style hard refresh) whereas setting location.href back to href (or pathname or URL) does not, which could be a significant (and unnecessary) difference in load time on some pages.
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MySQL load NULL values from CSV data
...one, two, three, @vfour, five)
SET four = NULLIF(@vfour,'')
;
If they're all possibly empty, then you'd read them all into variables and have multiple SET statements, like this:
LOAD DATA INFILE '/tmp/testdata.txt'
INTO TABLE moo
FIELDS TERMINATED BY ","
LINES TERMINATED BY "\n"
(@vone, @vtwo, @v...
Is non-blocking I/O really faster than multi-threaded blocking I/O? How?
...ocking or asynchronous I/O is that your thread can continue its work in parallel. Of course you can achieve this also using an additional thread. As you stated for best overall (system) performance I guess it would be better to use asynchronous I/O and not multiple threads (so reducing thread switch...
Free space in a CMD shell
...unt of free diskspace of a disk or a folder in a CMD
without having to install some thirdparty applications?
9 Answers
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Haversine Formula in Python (Bearing and Distance between two GPS points)
...fy math.pi, math.sin etc. With from math import * you get direct access to all the module contents. Check out "namespaces" in a python tutorial (such as docs.python.org/tutorial/modules.html)
– Michael Dunn
Feb 6 '11 at 21:20
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How to “properly” create a custom object in JavaScript?
...e result is that in mixed company you will have a mishmash of metaclasses, all behaving slightly differently. What's worse, most JavaScript tutorial material is terrible and serves up some kind of in-between compromise to cover all bases, leaving you very confused. (Probably the author is also confu...