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bool operator ++ and --
... supports ++ (increment) for bool, but not -- (decrement). It this just a random decision, or there is some reason behind this?
...
What's the cause of this FatalExecutionEngineError in .NET 4.5 beta? [closed]
...ecutionEngineError exception. I spent a good 30 minutes trying to isolate and minimize the culprit sample. Compile this using Visual Studio 2012 as a console app:
...
Python __str__ versus __unicode__
...tted and someone calls unicode(o) or u"%s"%o, Python calls o.__str__() and converts to unicode using the system encoding. (See documentation of __unicode__().)
The opposite is not true. If you implement __unicode__() but not __str__(), then when someone calls str(o) or "%s"%o, Python returns repr...
Adding placeholder text to textbox
...;
myTxtbx.Text = "Enter text here...";
myTxtbx.GotFocus += GotFocus.EventHandle(RemoveText);
myTxtbx.LostFocus += LostFocus.EventHandle(AddText);
public void RemoveText(object sender, EventArgs e)
{
if (myTxtbx.Text == "Enter text here...")
{
myTxtbx.Text = "";
}
}
public void A...
How can I loop through a C++ map of maps?
...ing answers are outdated as of C++11 - you can use a ranged based for loop and simply do:
std::map<std::string, std::map<std::string, std::string>> mymap;
for(auto const &ent1 : mymap) {
// ent1.first is the first key
for(auto const &ent2 : ent1.second) {
// ent2.first ...
How to detect when an Android app goes to the background and come back to the foreground
...
The onPause() and onResume() methods are called when the application is brought to the background and into the foreground again. However, they are also called when the application is started for the first time and before it is killed. You ...
Mercurial move changes to a new branch
...et's say the changesets to move are revisions 1-3:
hg qimport -r 1:3 # convert revisions to patches
hg qpop -a # remove all them from history
hg branch new # start a new branch
hg qpush -a # push them all back into history
hg qfin -a # finalize the patches
...
Why should I use a pointer rather than the object itself?
I'm coming from a Java background and have started working with objects in C++. But one thing that occurred to me is that people often use pointers to objects rather than the objects themselves, for example this declaration:
...
How to track down a “double free or corruption” error
...You can set this from gdb by using the set environment MALLOC_CHECK_ 2 command before running your program; the program should abort, with the free() call visible in the backtrace.
see the man page for malloc() for more information
...
Parallel.ForEach vs Task.Factory.StartNew
...roduce far more overhead than necessary, especially for large collections, and cause the overall runtimes to be slower.
FYI - The Partitioner used can be controlled by using the appropriate overloads to Parallel.ForEach, if so desired. For details, see Custom Partitioners on MSDN.
The main differ...