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When should I really use noexcept?
...now if the function will throw. For a reminder, any kind of dynamic memory allocation may throw.
Okay, now on to the possible optimizations.
The most obvious optimizations are actually performed in the libraries. C++11 provides a number of traits that allows knowing whether a function is noexcep...
How do I concatenate const/literal strings in C?
...nnot be used as a buffer, since it is a constant. Thus, you always have to allocate a char array for the buffer.
The return value of strcat can simply be ignored, it merely returns the same pointer as was passed in as the first argument. It is there for convenience, and allows you to chain the call...
Explaining difference between automaticallyAdjustsScrollViewInsets, extendedLayoutIncludesOpaqueBars
...it with an example:
UIViewController *viewController = [[UIViewController alloc] init];
viewController.view.backgroundColor = [UIColor redColor];
UINavigationController *mainNavigationController = [[UINavigationController alloc] initWithRootViewController:viewController];
Here you are not setting...
How do I get the result of a command in a variable in windows?
...ple i gave with the 'CD' command.
set _readfile=test.txt
for /f "usebackq tokens=2 delims=:" %%a in (`find /c /v "" %_readfile%`) do set _max=%%a
set /a _max+=1
set _i=0
set _filename=temp.dat
rem ---------
rem Make the list
rem ---------
:makeList
find /n /v "" %_readfile% >%_filename%
rem -...
How to repeat a string a variable number of times in C++?
...ster implementation, the idea is to minimise copying operations and memory allocations by first exponentially growing the string:
#include <string>
#include <cstddef>
std::string repeat(std::string str, const std::size_t n)
{
if (n == 0) {
str.clear();
str.shrink_to...
How to throw std::exceptions with variable messages?
...hich can cause an exception.
Generally, there is no difference whether you allocate memory (work with strings in C++ manner) in the constructor of the exception or just before throwing - std::bad_alloc exception can be thrown before the one which you really want.
So, a buffer allocated on the stack ...
Efficient way to remove ALL whitespace from String?
...planation as to what this expression means, \s means "match any whitespace token", and + means "match one or more of the proceeding token". Also RegExr is a nice website to practice writing RegEx expressions with, if you want to experiment.
– jrh
Oct 31 '17 at...
How to write a scalable Tcp/Ip based server
....
The main feature of these enhancements is the avoidance of the repeated allocation and synchronization of objects during high-volume asynchronous socket I/O. The Begin/End design pattern currently implemented by the System.Net.Sockets..::.Socket class requires a System..::.IAsyncResult object be ...
What is the difference between visibility:hidden and display:none?
...h you can still interact with it through the dom). There will be no space allocated for it between the other tags.
visibility:hidden means that unlike display:none, the tag is not visible, but space is allocated for it on the page. The tag is rendered, it just isn't seen on the page.
For exampl...
What is a pre-revprop-change hook in SVN, and how do I create it?
... sure that the new svn:log message is not empty.
set bIsEmpty=true
for /f "tokens=*" %%g in ('find /V ""') do (
set bIsEmpty=false
)
if "%bIsEmpty%" == "true" goto ERROR_EMPTY
goto :eof
:ERROR_EMPTY
echo Empty svn:log messages are not allowed. >&2
goto ERROR_EXIT
:ERROR_PROPNAME
echo Only ...