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What is the performance cost of having a virtual method in a C++ class?
...3ghz in-order PowerPC processor. On that architecture, a virtual function call costs 7 nanoseconds longer than a direct (non-virtual) function call.
So, not really worth worrying about the cost unless the function is something like a trivial Get()/Set() accessor, in which anything other than inli...
What is the difference between NTFS Junction Points and Symbolic Links?
...nks is that Junctions are only able to be directories, while SymLinks are allowed to also target files.
6 Answers
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How to set default value for form field in Symfony2?
..., it will also always force the value under any context. Not what I would call a "default value"...
– Hubert Perron
Apr 3 '13 at 18:25
4
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Can I protect against SQL injection by escaping single-quote and surrounding user input with single-
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First of all, it's just bad practice. Input validation is always necessary, but it's also always iffy.
Worse yet, blacklist validation is always problematic, it's much better to explicitly and strictly define what values/formats you a...
One or more types required to compile a dynamic expression cannot be found. Are you missing referenc
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The Visual Studio team should really think about letting people mouse over the error and then select "Add Microsoft.CSharp to References"
– geoyws
May 12 '14 at 7:04
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Can grep show only words that match search pattern?
... grep across a number of directories it did display the full file path for all matched files, whereas with -h it just displayed the matched words without any specification about which file it is. So, to match the original question, I think it is necessary in certain circumstances.
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Android getting value from selected radiobutton
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Just a small correction, a very small one rather, you have declared 'rg' twice. It wont make a difference at all, just makes the code more readable.
– SanVed
Aug 19 '18 at 18:06
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Can I use assert on Android devices?
...t.
You can do
import static junit.framework.Assert.*;
now you can use all the functions like assertTrue, assertEquals, assertNull that are provided in the junit framework.
Be careful not to import the Junit4 framework through eclipse, that would be the org.junit package. You have to use the j...
How can I make a UITextField move up when the keyboard is present - on starting to edit?
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isn't it batter to call -(void)setViewMovedUp:(BOOL)movedUp in keyBoardWillSHow and KeyBoardWillHide events!!
– Abduliam Rehmanius
Jun 26 '11 at 4:08
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Which is the preferred way to concatenate a string in Python?
...b):
0.0132720470428
a.join(a):
0.114929914474
Well, append/join is marginally faster there if you are using extremely long strings (which you usually aren't, what would you have a string that's 100MB in memory?)
But the real clincher is Python 2.3. Where I won't even show you the timings, because...