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Standard alternative to GCC's ##__VA_ARGS__ trick?
There is a well-known problem with empty args for variadic macros in C99.
10 Answers
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How to compare type of an object in Python?
...ou can always use the type(x) == type(y) trick, where y is something with known type.
# check if x is a regular string
type(x) == type('')
# check if x is an integer
type(x) == type(1)
# check if x is a NoneType
type(x) == type(None)
Often there are better ways of doing that, particularly with an...
How to get screen dimensions as pixels in Android
...n API level 13), you could use the getWidth and getHeight methods that are now deprecated:
Display display = getWindowManager().getDefaultDisplay();
int width = display.getWidth(); // deprecated
int height = display.getHeight(); // deprecated
For the use case you're describing however, a margi...
When does invoking a member function on a null instance result in undefined behavior?
...d a weak "use a dereferenced null pointer, get undefined behavior" view.
Now we consider the question.
Yes, (a) results in undefined behavior. In fact, if this is null then regardless of the contents of the function the result is undefined.
This follows from §5.2.5/3:
If E1 has the type ...
Combining CSS Pseudo-elements, “:after” the “:last-child”
...
I know you've probably long forgotten this particular thread, but since you mentioned that your lists were of variable length it's worth pointing out that, in most contexts, a list with exactly two items wouldn't be correct with...
Mipmap drawables for icons
Since Android 4.3 (Jelly Bean) we can now make use of the res/mipmap folders to store "mipmap" images.
11 Answers
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What is a segmentation fault?
...nd introducing hard-to-debug memory bugs. Whenever you get a segfault you know you are doing something wrong with memory – accessing variable that has already been freed, writing to a read-only portion of the memory, etc. Segmentation fault is essentially the same in most languages that let you me...
Apply CSS styles to an element depending on its child elements
...ion which is "Is there a way to do this with CSS". It clearly states: "I know I can achieve this using javascript, but I just wondered whether this is possible using some unknown (to me) CSS features."
– SunshinyDoyle
Aug 28 '18 at 14:27
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“git rm --cached x” vs “git reset head -- x”?
... commit it, you add it to the tree as well.
It will probably help you to know the three more common flags in git reset:
git reset [--<mode>] [<commit>]
This form resets the current branch head to <commit> and possibly
updates the index (resetting it to the tree of <...
How do I convert an existing callback API to promises?
...ferreds you can do the following (let's use Q for this example, although Q now supports the new syntax which you should prefer):
function getStuffAsync(param) {
var d = Q.defer();
getStuff(param, function(err, data) {
if (err !== null) d.reject(err);
else d.resolve(data);
...