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What are all the uses of an underscore in Scala?
...s taken on scala-lang.org and noticed a curious question: " Can you name all the uses of “_”? ". Can you? If yes, please do so here. Explanatory examples are appreciated.
...
Django: Get list of model fields?
...s which (ultimately) inherits from models.Model . I want to get a list of all the fields defined for this model. For example, phone_number = CharField(max_length=20) . Basically, I want to retrieve anything that inherits from the Field class.
...
node.js, socket.io with SSL
... your initial connection, i.e. instead of "http://" use "https://". If the WebSocket transport is chosen, then Socket.IO should automatically use "wss://" (SSL) for the WebSocket connection too.
Update:
You can also try creating the connection using the 'secure' option:
var socket = io.connect('h...
Why aren't superclass __init__ methods automatically invoked?
...thon designers decide that subclasses' __init__() methods don't automatically call the __init__() methods of their superclasses, as in some other languages? Is the Pythonic and recommended idiom really like the following?
...
C# version of java's synchronized keyword?
... be thread-safe. Use YAGNI: only apply thread-safety when you know you actually are going to use it (and test it).
For the method-level stuff, there is [MethodImpl]:
[MethodImpl(MethodImplOptions.Synchronized)]
public void SomeMethod() {/* code */}
This can also be used on accessors (properties ...
how to convert array values from string to int?
...ng and closure/anonymous callback would do...
– jave.web
Oct 12 '18 at 19:27
array_map(function($v){ return (int)$v; }...
What are the differences between NP, NP-Complete and NP-Hard?
... the technical definitions require quite some time to understand. First of all, let's remember a preliminary needed concept to understand those definitions.
Decision problem: A problem with a yes or no answer.
Now, let us define those complexity classes.
P
P is a complexity class that repres...
Apache: client denied by server configuration
...pache. You can see the enabling of the feature with the directive
Require all denied
This basically says to deny access to all users. To fix this problem, either remove the denied directive (or much better) add the following directive to the directories you want to grant access to:
Require all g...
Calling parent class __init__ with multiple inheritance, what's the right way?
...ing super() leads to greater flexibility for subclasses.
In the direct call approach, C.__init__ can call both A.__init__ and B.__init__.
When using super(), the classes need to be designed for cooperative multiple inheritance where C calls super, which invokes A's code which will also call supe...
Why use symbols as hash keys in Ruby?
...saves memory, because they are only stored once.
Symbols in Ruby are basically "immutable strings" .. that means that they can not be changed, and it implies that the same symbol when referenced many times throughout your source code, is always stored as the same entity, e.g. has the same object id...