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Does Dart support enumerations?
...ase Fruit.apple:
print('it is an apple');
break;
}
// get all the values of the enums
for (List<Fruit> value in Fruit.values) {
print(value);
}
// get the second value
print(Fruit.values[1]);
}
The old approach before 1.8:
class Fruit {
static const APPLE =...
How to write header row with csv.DictWriter?
...ion "functionality", I'd prefer to code it myself; that way you can report ALL "extras" with the keys and values, not just the first extra key. What is a real nuisance with DictWriter is that if you've verified the keys yourself as each dict was being built, you need to remember to use extrasaction=...
Make sure that the controller has a parameterless public constructor error
...
What's happening is that you're bitten by this problem. Basically, what happened is that you didn't register your controllers explicitly in your container. Unity tries to resolve unregistered concrete types for you, but because it can't resolve it (caused by an error in your configurat...
How do I correctly clone a JavaScript object?
... if you know its name, but I don't know of any way to discover it automatically.
Yet another snag in the quest for an elegant solution is the problem of setting up the prototype inheritance correctly. If your source object's prototype is Object, then simply creating a new general object with {} wil...
ActiveMQ or RabbitMQ or ZeroMQ or [closed]
... If no wire protocol assumed: see other answers.
– Fletch
Dec 2 '10 at 10:53
19
Having worked in ...
Why do you need explicitly have the “self” argument in a Python method?
... to make things like this explicit rather than based on a rule.
Additionally, since nothing is implied or assumed, parts of the implementation are exposed. self.__class__, self.__dict__ and other "internal" structures are available in an obvious way.
...
Is there a function to make a copy of a PHP array to another?
...ewLarsson raises a point in the comments below. PHP has a special feature called "references". They are somewhat similar to pointers in languages like C/C++, but not quite the same. If your array contains references, then while the array itself is passed by copy, the references will still resolve to...
Why rename synthesized properties in iOS with leading underscores? [duplicate]
...s is an artifact of a previous version of the Objective-C runtime.
Originally, @synthesize was used to create accessors methods, but the runtime still required that instance variables had to be instantiated explicitly:
@interface Foo : Bar {
Baz *_qux;
}
@property (retain) Baz *qux;
@end
@imp...
Is explicitly closing files important?
In Python, if you either open a file without calling close() , or close the file but not using try - finally or the " with " statement, is this a problem? Or does it suffice as a coding practice to rely on the Python garbage-collection to close all files? For example, if one does this:
...
Private and Protected Members : C++
...
Public members of a class A are accessible for all and everyone.
Protected members of a class A are not accessible outside of A's code, but is accessible from the code of any class derived from A.
Private members of a class A are not accessible outside of A's code, or f...