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Where does Scala look for implicits?
...bout the latter type, if one calls a method m on an object o of a class C, and that class does not support method m, then Scala will look for an implicit conversion from C to something that does support m. A simple example would be the method map on String:
"abc".map(_.toInt)
String does not supp...
load and execute order of scripts
...ipts are held until all external scripts that came before them have loaded and run.
Async scripts (regardless of how they are specified as async) load and run in an unpredictable order. The browser loads them in parallel and it is free to run them in whatever order it wants.
There is no predictab...
Performance of static methods vs instance methods
...g to the performance characteristics of static methods vs instance methods and their scalability. Assume for this scenario that all class definitions are in a single assembly and that multiple discrete pointer types are required.
...
Accessing member of base class
...e super keyword in order to avoid confusion between a specialised function and the base class function. For example, if you called move() or this.move() you would be dealing with the specialised Snake or Horse function, so using super.move() explicitly calls the base class function.
There is no con...
ASP.NET MVC How to convert ModelState errors to json
...;
}
return null;
}
}
Then call that extension method and return the errors from the controller action (if any) as json:
if (!ModelState.IsValid)
{
return Json(new { Errors = ModelState.Errors() }, JsonRequestBehavior.AllowGet);
}
And then finally, show those errors on th...
callback to handle completion of pipe
I am using the following node.js code to download documents from some url and save it in the disk.
I want to be informed about when the document is downloaded. i have not seen any callback with pipe.Or, Is there any 'end' event that can be captured on completion of download ?
...
How do negative margins in CSS work and why is (margin-top:-5 != margin-bottom:5)?
...
Negative margins are valid in css and understanding their (compliant) behaviour is mainly based on the box model and margin collapsing. While certain scenarios are more complex, a lot of common mistakes can be avoided after studying the spec.
For instance, r...
If I fork someone else's private Github repo into my account, is it going to appear in my account as
...
No. You can fork it and it still remains private.
Private collaborators may fork any private repository you’ve added
them to without their own paid plan. Their forks do not count against
your private repository quota.
https://github....
Fastest way to get the first object from a queryset in django?
...
Use the convenience methods .first() and .last():
MyModel.objects.filter(blah=blah).first()
They both swallow the resulting exception and return None if the queryset returns no objects.
These were added in Django 1.6, which was released in Nov 2013.
...
How often does python flush to a file?
... to use the system default, which is usually line buffered for tty devices and fully buffered for other files.
If omitted, the system default is used.
code:
bufsize = 0
f = open('file.txt', 'w', buffering=bufsize)
shar...