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How much is too much with C++11 auto keyword?
...ng side effects, then it must be good to do so.
Counterexamples (borrowed from someone else's answers):
auto i = SomeClass();
for (auto x = make_unsigned (y); ...)
Here we DO care what the type is, so we should write Someclass i; and for(unsigned x = y;...
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runOnUiThread in fragment
... @developer1011 that will happen when the fragment has been detached from the activity. This is common in async tasks, because the activity could have been destroyed during the long running operation, so it no longer exists to get. Always check for null first.
– bclymer
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C++0x has no semaphores? How to synchronize threads?
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You can easily build one from a mutex and a condition variable:
#include <mutex>
#include <condition_variable>
class semaphore
{
private:
std::mutex mutex_;
std::condition_variable condition_;
unsigned long count_ = 0; // In...
Rails how to run rake task
...
You can run Rake tasks from your shell by running:
rake task_name
To run from from Ruby (e.g., in the Rails console or another Rake task):
Rake::Task['task_name'].invoke
To run multiple tasks in the same namespace with a single task, create t...
Fast way to get image dimensions (not filesize)
...ions also PPM, WEBP), and does only read the header.
The identify command (from ImageMagick) prints lots of image information for a wide variety of images. It seems to restrain itself to reading the header portion (see comments). It also has a unified output which file sadly lacks.
exiv2 gives you d...
PHP编译configure时常见错误 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...d.
apt-get install libpng12-dev
6、configure: error: cannot find output from lex; giving up
yum -y install flex
7、configure: error: mod_deflate has been requested but can not be built due to prerequisite failures
centos: yum -y install zlib-devel openssl-devel
debian: apt-get install zlib1g...
How to pass objects to functions in C++?
... optional value should not be modified)
There are other small deviations from these rules, the first of which is handling ownership of an object. When an object is dynamically allocated with new, it must be deallocated with delete (or the [] versions thereof). The object or function that is respon...
NSLog/printf specifier for NSInteger?
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So the only thing you can do unfortunately: Use %ld, and cast your values from NSInteger to long, or from NSUInteger to unsigned long.
Once you don't build for 32 bit anymore, you can just use %ld, without any cast.
shar...
Getting file size in Python? [duplicate]
...enericpath.py').st_size
Or use Path(path).stat().st_size (Python 3.4+)
from pathlib import Path
Path('C:\\Python27\\Lib\\genericpath.py').stat().st_size
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Access to Modified Closure (2)
This is an extension of question from Access to Modified Closure . I just want to verify if the following is actually safe enough for production use.
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