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__proto__ VS. prototype in JavaScript
...x = x;
this.y = y;
}
var myPoint = new Point();
// the following are all true
myPoint.__proto__ == Point.prototype
myPoint.__proto__.__proto__ == Object.prototype
myPoint instanceof Point;
myPoint instanceof Object;
Here Point is a constructor function, it builds an object (data structure) p...
From an array of objects, extract value of a property as array
...ere is a shorter way of achieving it:
let result = objArray.map(a => a.foo);
OR
let result = objArray.map(({ foo }) => foo)
You can also check Array.prototype.map().
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Get class that defined method
...ited Jun 20 '14 at 19:44
Aaron Hall♦
260k6969 gold badges353353 silver badges303303 bronze badges
answered Jun 7 '09 at 2:23
...
How to convert a std::string to const char* or char*?
... Notice that the above is not exception safe. If anything between the new call and the delete call throws, you will leak memory, as nothing will call delete for you automatically. There are two immediate ways to solve this.
boost::scoped_array
boost::scoped_array will delete the memory for you upo...
Is there a decorator to simply cache function return values?
...maxsize=100, typed=False)
Decorator to wrap a function with a memoizing callable that saves up to the maxsize most recent calls. It can save time when an expensive or I/O bound function is periodically called with the same arguments.
Example of an LRU cache for computing Fibonacci numbers:
@lru...
JavaScript: What are .extend and .prototype used for?
...ate ).lol() // alert message
In the snippet above, I define a method for all Date objects ( already existing ones and all new ones ).
extend is usually a high level function that copies the prototype of a new subclass that you want to extend from the base class.
So you can do something like:
e...
Concatenating two lists - difference between '+=' and extend()
I've seen there are actually two (maybe more) ways to concatenate lists in Python:
One way is to use the extend() method:
9...
How does the @property decorator work in Python?
... the @decorator syntax is just syntactic sugar; the syntax:
@property
def foo(self): return self._foo
really means the same thing as
def foo(self): return self._foo
foo = property(foo)
so foo the function is replaced by property(foo), which we saw above is a special object. Then when you use @...
Ubuntu, vim, and the solarized color palette
I'd really like to get in on all the colorful goodness of the solarized colorscheme , but I can't seem to get it configured just right.
I have the main solarized file in my .vim/colors folder, I've set my terminal profile colors to what is listed on the site, and I've added the lines
...
What does Expression.Quote() do that Expression.Constant() can’t already do?
...pression.Add(ps, pt),
pt)),
ps);
var f2a = (Func<int, Expression<Func<int, int>>>)ex2.Compile();
var f2b = f2a(200).Compile();
Console.WriteLine(f2b(123));
And indeed, if you compile and run this code you get the right answer.
...