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Rails :dependent => :destroy VS :dependent => :delete_all
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The difference is with the callback.
The :delete_all is made directly in your application and deletes by SQL :
DELETE * FROM users where compagny_id = XXXX
With the :destroy, there is an instantiation of all of your children. So, if you can't destro...
Ruby on Rails Server options [closed]
..., Mongrel, Passenger, Apache, Nginx and many more I am sure, and I don't really understand the different roles they play.
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How do I expand a tuple into variadic template function's arguments?
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Here's my code if anyone is interested
Basically at compile time the compiler will recursively unroll all arguments in various inclusive function calls <N> -> calls <N-1> -> calls ... -> calls <0> which is the last one and the compiler will o...
unbound method f() must be called with fibo_ instance as first argument (got classobj instance inste
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OK, first of all, you don't have to get a reference to the module into a different name; you already have a reference (from the import) and you can just use it. If you want a different name just use import swineflu as f.
Second, you are...
Remove last character of a StringBuilder?
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@Harish - and possibly not at all, if the optimizer unrolls the first loop iteration.
– Stephen C
Aug 27 '12 at 14:28
7
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Execute and get the output of a shell command in node.js
...ng the output, without falling into a callback hell and with a pretty neat API. Using the await keyword, you can create a script that reads easily, while still be able to get the work of child_process.exec done.
Code sample
const childProcess = require("child_process");
/**
* @param {string} com...
Proper use of beginBackgroundTaskWithExpirationHandler
...l need to wrap it in a background task. It's also very important that you call endBackgroundTask when you're finished - otherwise the app will be killed after its allotted time has expired.
Mine tend look something like this:
- (void) doUpdate
{
dispatch_async(dispatch_get_global_queue(DISPAT...
How can I view all the git repositories on my machine?
Is there a way in which I can see all the git repositories that exist on my machine? Any command for that?
10 Answers
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How do I check if a string is valid JSON in Python?
...SON.
In general, the "Pythonic" philosophy for this kind of situation is called EAFP, for Easier to Ask for Forgiveness than Permission.
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Retrieve only the queried element in an object array in MongoDB collection
...r to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// Get just the docs that contain a shapes element where color is 'red'
{$match: {'shapes.color': 'red'}},
{$project: {
shapes: {$filter: {
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