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How to implement has_many :through relationships with Mongoid and mongodb?
...ther side. For example:
class Physician
include Mongoid::Document
has_and_belongs_to_many :patients
end
class Patient
include Mongoid::Document
has_and_belongs_to_many :physicians
end
In other words you would eliminate the join table and it would have a similar effect to has_many :throug...
How do I correctly clean up a Python object?
__del__(self) above fails with an AttributeError exception. I understand Python doesn't guarantee the existence of "global variables" (member data in this context?) when __del__() is invoked. If that is the case and this is the reason for the exception, how do I make sure the object destructs...
How to automatically crop and center an image
... any arbitrary image, I want to crop a square from the center of the image and display it within a given square.
7 Answers
...
What do hjust and vjust do when making a plot using ggplot?
...lot using ggplot, I spend a little while trying different values for hjust and vjust in a line like
2 Answers
...
What is the cleanest way to get the progress of JQuery ajax request?
...ng a request, processing the request in the backend to generate some data, and return it back. How can the client side possibly know what is being done in the backend and how much time it will take that it can calculate the progress?
– SexyBeast
Apr 30 '17 at 2...
What does “=>” mean in PHP?
...the context of that foreach loop, it assigns the key of the array to $user and the value to $pass.
Example:
$user_list = array(
'dave' => 'apassword',
'steve' => 'secr3t'
);
foreach ($user_list as $user => $pass) {
echo "{$user}'s pass is: {$pass}\n";
}
// Prints:
// "dave's...
Does C++ support 'finally' blocks? (And what's this 'RAII' I keep hearing about?)
...lock()
{
m_.release();
}
};
// A class which uses 'mutex' and 'lock' objects
class foo
{
mutex mutex_; // mutex for locking 'foo' object
public:
void bar()
{
lock scopeLock(mutex_); // lock object.
foobar(); // an operation which may throw an exception
...
Google Maps v3 - limit viewable area and zoom level
...a certain area? I want to allow displaying only some area (e.g. a country) and disallow the user to slide elsewhere. Also I want to restrict the zoom level - e.g. only between levels 6 and 9. And I want to use all the base map types.
...
What can I use instead of the arrow operator, `->`?
... them inconsistently. Becomes really annoying when you work with templates and don't know the precise type.
– Konrad Rudolph
Oct 21 '08 at 10:15
1
...
Does use of final keyword in Java improve the performance?
...s, HotSpot keeps track of whether the method has actually been overridden, and is able to perform optimizations such as inlining on the assumption that a method hasn't been overridden - until it loads a class which overrides the method, at which point it can undo (or partially undo) those optimizati...