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What is the difference between NULL, '\0' and 0?
...e appear to be differences between various values of zero -- NULL , NUL and 0 .
11 Answers
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How to combine class and ID in CSS selector?
...* Won't work in IE6, but valid */
div.firstClass.secondClass /* ditto */
and, per your example:
div#content.sectionA
Edit, 4 years later: Since this is super old and people keep finding it: don't use the tagNames in your selectors. #content.myClass is faster than div#content.myClass because the...
What is the Java ?: operator called and what does it do?
...
Yes, it is a shorthand form of
int count;
if (isHere)
count = getHereCount(index);
else
count = getAwayCount(index);
It's called the conditional operator. Many people (erroneously) call it the ternary operator, because it's the only te...
Threading in a PyQt application: Use Qt threads or Python threads?
...humb might be to use QThreads if you're going to interact somehow with Qt, and use Python threads otherwise.
And some earlier comment on this subject from PyQt's author: "they are both wrappers around the same native thread implementations". And both implementations use GIL in the same way.
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Why would anybody use C over C++? [closed]
...would want to choose C over C++. C doesn't seem to get nearly as much flak and if C++ has all these problems why can't you just restrict yourself to the C subset? What are your thoughts/experience?
...
Linux - Replacing spaces in the file names
I have a number of files in a folder, and I want to replace every space character in all file names with underscores. How can I achieve this?
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CSS Classes & SubClasses
...means:
Apply this style to any element that has both the class "area1" and "item".
Such as:
<div class="area1 item">
Sadly it doesn't work in IE6, but that's what it means.
share
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im...
How to migrate/convert from SVN to Mercurial (hg) on windows
...to migrate a couple of SVN repositories to Mercurial, with history, labels and so on.
9 Answers
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Is it safe to use -1 to set all bits to true?
...times have surprising behavior because you will have to have the right operand type. Only then you will get the most high value of an unsigned type.
For an example of a possible surprise, consider this one:
unsigned long a = ~0u;
It won't necessarily store a pattern with all bits 1 into a. But ...
What's the @ in front of a string in C#?
...string verbatim = @"foo\bar";
string regular = "foo\\bar";
Here verbatim and regular have the same contents.
It also allows multi-line contents - which can be very handy for SQL:
string select = @"
SELECT Foo
FROM Bar
WHERE Name='Baz'";
The one bit of escaping which is necessary for verbatim s...