大约有 45,000 项符合查询结果（耗时：0.0316秒） [XML]
How to prevent gcc optimizing some statements in C?
... memory stores and loads. One purpose of volatile is to let the compiler know that the memory access has side effects, and therefore must be preserved. In this case, the store has the side effect of causing a page fault, and you want the compiler to preserve the page fault.
This way, the surround...
Converting datetime.date to UTC timestamp in Python
...eturn (td.microseconds + (td.seconds + td.days * 86400) * 10**6) / 10**6
now = datetime.utcnow()
print now
print totimestamp(now)
Beware of floating-point issues.
Output
2012-01-08 15:34:10.022403
1326036850.02
How to convert an aware datetime object to POSIX timestamp
assert dt.tzinfo is n...
See line breaks and carriage returns in editor
Does anyone know of a text editor on Linux that allows me to see line breaks and carriage returns? Does Vim support this feature?
...
How to handle WndProc messages in WPF?
... lParam, ref bool handled)
{
// do stuff
return IntPtr.Zero;
}
Now, I'm not quite sure why you'd want to handle Windows Messaging messages in a WPF application (unless it's the most obvious form of interop for working with another WinForms app). The design ideology and the nature of the ...
Why is “import *” bad?
...espace (might shadow some other object from previous import and you won't know about it).
Because you don't know exactly what is imported and can't easily find from which module a certain thing was imported (readability).
Because you can't use cool tools like pyflakes to statically detect errors i...
Converting Long to Date in Java returns 1970
...nt of whole seconds since the same epoch reference of 1970-01-01T00:00Z.
Know Your Data
People use various precisions in tracking time as a number since an epoch. So when you obtain some numbers to be interpreted as a count since an epoch, you must determine:
What epoch?Many epochs dates have been...
What is the purpose of the word 'self'?
...stance attributes. That's why assigning to an instance attribute needs to know what instance to assign to, and that's why it needs self..
share
|
improve this answer
|
follow...
Overriding superclass property with different type in Swift
...ore than one superclass declaration
I've only checked Xcode 6.0 GM as of now.
Unfortunately, you'll have to wait until Apple fixes this.
I've submitted a bug report too. 18518795
share
|
improve...
What are the “standard unambiguous date” formats for string-to-date conversion in R?
...here a better solution than needing to specify the format?
Yes, there is now (ie in late 2016), thanks to anytime::anydate from the anytime package.
See the following for some examples from above:
R> anydate(c("01 Jan 2000", "01/01/2000", "2015/10/10"))
[1] "2000-01-01" "2000-01-01" "2015-10...
append to url and refresh page
...aram=42';
We don't have to alter the entire url, just the query string, known as the search attribute of location.
When you are assigning a value to the search attribute, the question mark is automatically inserted by the browser and the page is reloaded.
...