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MenuItemCompat.getActionView always returns null
...library but the MenuItemCompat.getActionView always return null in every Android version I tested (4.2.2, 2.3.4 ....)
11 ...
Why is the .bss segment required?
What I know is that global and static variables are stored in the .data segment, and uninitialized data are in the .bss segment. What I don't understand is why do we have dedicated segment for uninitialized variables? If an uninitialised variable has a value assigned at run time, does the varia...
Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
...s no such thing as "unsigned integer overflow") means undefined behaviour. And this means anything can happen, and discussing why does it happen under the rules of C++ doesn't make sense.
C++11 draft N3337: §5.4:1
If during the evaluation of an expression, the result is not mathematically de...
Why does the arrow (->) operator in C exist?
...
I'll interpret your question as two questions: 1) why -> even exists, and 2) why . does not automatically dereference the pointer. Answers to both questions have historical roots.
Why does -> even exist?
In one of the very first versions of C language (which I will refer as CRM for "C Refe...
What makes Scala's operator overloading “good”, but C++'s “bad”?
Operator overloading in C++ is considered by many to be A Bad Thing(tm), and a mistake not to be repeated in newer languages. Certainly, it was one feature specifically dropped when designing Java.
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Portable way to get file size (in bytes) in shell?
...at --format="%s" FILE , but Solaris I have access to doesn't have stat command. What should I use then?
14 Answers
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Iterating over every two elements in a list
...+ y)
In Python 3, you can replace izip with the built-in zip() function, and drop the import.
All credit to martineau for his answer to my question, I have found this to be very efficient as it only iterates once over the list and does not create any unnecessary lists in the process.
N.B: This ...
What does the explicit keyword mean?
...hat takes a Foo object:
void DoBar (Foo foo)
{
int i = foo.GetFoo ();
}
and here's where the DoBar function is called:
int main ()
{
DoBar (42);
}
The argument is not a Foo object, but an int. However, there exists a constructor for Foo that takes an int so this constructor can be used to conv...
How can I filter a date of a DateTimeField in Django?
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Looks like it will land in Django 1.9: github.com/django/django/commit/…
– amjoconn
Oct 22 '15 at 19:45
16
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powershell - extract file name and extension
I need to extract file name and extension from e.g. my.file.xlsx. I don't know the name of file or extension and there may be more dots in the name, so I need to search the string from the right and when I find first dot (or last from the left), extract the part on the right side and the part on the...