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std::unique_lock or std::lock_guard?
...er you need to relock the guard.
std::unique_lock has other features that allow it to e.g.: be constructed without locking the mutex immediately but to build the RAII wrapper (see here).
std::lock_guard also provides a convenient RAII wrapper, but cannot lock multiple mutexes safely. It can be us...
What is the point of noreturn?
...n attribute is supposed to be used for functions that don't return to the caller. That doesn't mean void functions (which do return to the caller - they just don't return a value), but functions where the control flow will not return to the calling function after the function finishes (e.g. function...
Is there a recommended format for multi-line imports?
...
Personally I go with parentheses when importing more than one component and sort them alphabetically. Like so:
from Tkinter import (
Button,
Canvas,
DISABLED,
END,
Entry,
Frame,
LEFT,
NORMAL,
RI...
Why doesn't delete set the pointer to NULL?
...
Stroustrup himself answers. An excerpt:
C++ explicitly allows an
implementation of delete to zero out
an lvalue operand, and I had hoped
that implementations would do that,
but that idea doesn't seem to have
become popular with implementers.
But the main issue he rais...
Is there a portable way to print a message from the C preprocessor?
...ng is not going to be great, as warnings are treated as errors for us generally, and we'd really like the message to be informational, rather than stop the compilation.
– Danny S
Mar 23 '15 at 4:10
...
What does map(&:name) mean in Ruby?
...
It's shorthand for tags.map(&:name.to_proc).join(' ')
If foo is an object with a to_proc method, then you can pass it to a method as &foo, which will call foo.to_proc and use that as the method's block.
The Symbol#to_proc method was originally added by ActiveSupport but has be...
How do I disable the resizable property of a textarea?
... elements:
textarea {
resize: none;
}
To disable it for some (but not all) textareas, there are a couple of options.
To disable a specific textarea with the name attribute set to foo (i.e., <textarea name="foo"></textarea>):
textarea[name=foo] {
resize: none;
}
Or, using an id...
SetUnhandledExceptionFilter and the C/C++ Runtime Library - C/C++ - 清...
...unctionality by the means of the SetUnhandledExceptionFilter function.
Usually, the SetUndhandledExceptionFilter function is used in conjunction with the crash reporting activity. Having the ability of pinpointing the line of code which caused a crash is invaluable in post mortem debugging.
Post m...
Difference between clustered and nonclustered index [duplicate]
...
You really need to keep two issues apart:
1) the primary key is a logical construct - one of the candidate keys that uniquely and reliably identifies every row in your table. This can be anything, really - an INT, a GUID, a string...
Vim: faster way to select blocks of text in visual mode
...elect from your current position to the next instance of "foo." If you actually wanted to expand to the next instance of "foo," on line 35, for example, just press n to expand selection to the next instance, and so on.
update
I don't often do it, but I know that some people use marks extensively to ...