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How to forward declare a template class in namespace std?
...served for use by the implementation, so you should use something like TEST_H instead of __TEST__. It's not going to generate a warning or an error, but if your program has a clash with an implementation-defined identifier, then it's not guaranteed to compile or run correctly: it's ill-formed. Also ...
Why can't I define a default constructor for a struct in .NET?
...ublic struct Tempo
{
const double DefaultBpm = 120;
private double _bpm; // this field must not be modified other than with its property.
public double BeatsPerMinute
{
get => _bpm + DefaultBpm;
set => _bpm = value - DefaultBpm;
}
}
This is different than...
Can I call memcpy() and memmove() with “number of bytes” set to zero?
...
From the C99 standard (7.21.1/2):
Where an argument declared as size_t n specifies the length of the array for a
function, n can have the value zero on a call to that function. Unless explicitly stated
otherwise in the description of a particular function in this subclause, pointer argume...
Delete directories recursively in Java
... .forEach(File::delete);
We use a comparator for reversed order, otherwise File::delete won't be able to delete possibly non-empty directory. So, if you want to keep directories and only delete files just remove the comparator in sorted() or remove sorting completely and add files f...
What is 'Context' on Android?
...ation class keeps tracks of a list of Activities that it’s monitoring in order to do its work. This list is used to coordinate all of the activities and make sure everything runs smoothly in managing the flow of activities.
There are some operations that I haven’t fully looked into which coordi...
What kind of leaks does automatic reference counting in Objective-C not prevent or minimize?
...chain referring back to an earlier object.
It is for this reason that the __unsafe_unretained and __weak ownership qualifiers exist. The former will not retain any object it points to, but leaves open the possibility of that object going away and it pointing to bad memory, whereas the latter doesn...
Fixing “Lock wait timeout exceeded; try restarting transaction” for a 'stuck" Mysql table?
...running transactions with
SELECT * FROM `information_schema`.`innodb_trx` ORDER BY `trx_started`
Your transaction should be one of the first, because it's the oldest in the list. Now just take the value from trx_mysql_thread_id and send it the KILL command:
KILL 1234;
If you're unsure which tr...
AngularJS : How do I switch views from a controller function?
...
In order to switch between different views, you could directly change the window.location (using the $location service!) in
index.html file
<div ng-controller="Cntrl">
<div ng-click="changeView('edit')">
...
Why does the MongoDB Java driver use a random number generator in a conditional?
... laws it is a trivial observation that this piece of code amounts to
if (!_ok && Math.random() <= 0.1)
return res;
The commit that originally introduced this logic had
if (_ok == true) {
_logger.log( Level.WARNING , "Server seen down: " + _addr, e );
} else if (Math.random() < 0...
I forgot the password I entered during postgres installation
...s to keep around
cp pg_hba.conf-backup pg_hba.conf
restart the server, in order to run with the safe pg_hba.conf
sudo /etc/init.d/postgresql restart
Further Reading about that pg_hba file: http://www.postgresql.org/docs/9.1/static/auth-pg-hba-conf.html
...