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Get all related Django model objects
...his gives you the property names for all related objects:
links = [rel.get_accessor_name() for rel in a._meta.get_all_related_objects()]
You can then use something like this to get all related objects:
for link in links:
objects = getattr(a, link).all()
for object in objects:
# d...
Create singleton using GCD's dispatch_once in Objective-C
...er here: instancetype
+ (instancetype)sharedInstance
{
static dispatch_once_t once;
static id sharedInstance;
dispatch_once(&once, ^
{
sharedInstance = [self new];
});
return sharedInstance;
}
+ (Class*)sharedInstance
{
static dispatch_once_t once;
...
Fastest way to copy file in node.js
...l disk during write)? Then reject will be called twice. A Promise solution based on Mike's answer with a flag (unfortunately) seems to be the only viable solution that properly considers error handling.
– Lekensteyn
May 24 '15 at 13:15
...
What's the best way to parse command line arguments? [closed]
...ter on.
Here's a typical line to add an option to your parser:
parser.add_option('-q', '--query',
action="store", dest="query",
help="query string", default="spam")
It pretty much speaks for itself; at processing time, it will accept -q or --query as options, store the ar...
How do I concatenate strings and variables in PowerShell?
... whitespace between $assoc.Id and " (et al). That is, option 1 gives you Id__-__Name__-__Owner (two spaces on each side of each -), but option 3 gives Id___-___Name___-___Owner (three spaces).
– ruffin
Dec 17 '14 at 15:10
...
How do you build a Singleton in Dart?
...t's easy to build a singleton:
class Singleton {
static final Singleton _singleton = Singleton._internal();
factory Singleton() {
return _singleton;
}
Singleton._internal();
}
You can construct it like this
main() {
var s1 = Singleton();
var s2 = Singleton();
print(identical(...
Why is `std::move` named `std::move`?
...
template <class T>
void
swap(T& a, T& b)
{
T tmp(static_cast<T&&>(a));
a = static_cast<T&&>(b);
b = static_cast<T&&>(tmp);
}
One has to recall that at this point in history, the only thing that "&&" could possibly mean w...
Recursively add files by pattern
...
The Windows port of zsh is based on a very old version and crashes all the time (for example when I enter ls).
– Michel Krämer
May 18 '10 at 8:09
...
Should import statements always be at the top of a module?
...ent libraries, don't break if an optional library is not installed.
In the __init__.py of a plugin, which might be imported but not actually used. Examples are Bazaar plugins, which use bzrlib's lazy-loading framework.
shar...
Where and how is the _ViewStart.cshtml layout file linked?
...rting with the ASP.NET MVC 3 Beta release, you can now add a file
called _ViewStart.cshtml (or _ViewStart.vbhtml for VB) underneath the
\Views folder of your project:
The _ViewStart file can be used to define common view code that you
want to execute at the start of each View’s renderin...