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Correct way to use get_or_create?
...f the fields have to be included in defaults. In case CREATE event occurs, all the fields are taken into consideration.
It looks like you need to be returning into a tuple, instead of a single variable, do like this:
customer.source,created = Source.objects.get_or_create(name="Website")
...
Distinct not working with LINQ to Objects
...
LINQ Distinct is not that smart when it comes to custom objects.
All it does is look at your list and see that it has two different objects (it doesn't care that they have the same values for the member fields).
One workaround is to implement the IEquatable interface as shown here.
If yo...
[科普] __MACOSX是什么文件夹？ - 更多技术 - 清泛网 - 专注C/C++及内核技术
[科普] __MACOSX是什么文件夹？（如图，一般的设计源文件都会有__MACOSX这个目录）以下为网上搜到的资料：MacOS作为他们的开发环境。例如，许多来自领先的网络框架组织的...
（如图，一般的设计源文件都会有__MACOSX这个目录）
...
Easiest way to convert int to string in C++
...icking up a discussion with @v.oddou a couple of years later, C++17 has finally delivered a way to do the originally macro-based type-agnostic solution (preserved below) without going through macro uglyness.
// variadic template
template < typename... Args >
std::string sstr( Args &&....
Passing Data between View Controllers
...h it onto nav stack.
ViewControllerB *viewControllerB = [[ViewControllerB alloc] initWithNib:@"ViewControllerB" bundle:nil];
viewControllerB.isSomethingEnabled = YES;
[self pushViewController:viewControllerB animated:YES];
This will set isSomethingEnabled in ViewControllerB to BOOL value YES.
P...
How should one use std::optional?
...std::string s, int& i);
Another way that this could be done is especially bad:
int* try_parse_int(std::string s); //return nullptr if fail
This requires dynamic memory allocation, worrying about ownership, etc. - always prefer one of the other two signatures above.
Another example:
clas...
upstream sent too big header while reading response header from upstream
... to increase the proxy_buffer_size and the proxy_buffers, or disable it totally (Please read the nginx documentation).
Example of proxy buffering configuration
http {
proxy_buffer_size 128k;
proxy_buffers 4 256k;
proxy_busy_buffers_size 256k;
}
Example of disabling your proxy buffer ...
How to schedule a function to run every hour on Flask?
...om apscheduler.schedulers.background import BackgroundScheduler
def print_date_time():
print(time.strftime("%A, %d. %B %Y %I:%M:%S %p"))
scheduler = BackgroundScheduler()
scheduler.add_job(func=print_date_time, trigger="interval", seconds=3)
scheduler.start()
# Shut down the scheduler when ...
Does ruby have real multithreading?
...ing
models.
(Unfortunately, only two of those 11 implementations are actually
ready for production use, but by the end of the year that number
will probably go up to four or five.) (Update: it's now 5: MRI, JRuby, YARV (the interpreter for Ruby 1.9), Rubinius and IronRuby).
The first implement...
Scala: write string to file in one statement
...or encoding-safe. If an exception happens in write(), close will never be called, and the file won't be closed. PrintWriter also uses the default system encoding, which is very bad for portability. And finally, this approach generates a separate class specifically for this line (however, given that ...