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What it the significance of the Javascript constructor property?
...reate your object. If you typed new Bar() it will be Bar and you typed new Fooit will be Foo.
The prototype
The prototype property is used for lookup in case the object in question does not have the property asked for. If you write x.attr, JavaScript will try to find attr among x's attributes. If ...
How does the “this” keyword work?
...is
Simple function invocation
Consider the following function:
function foo() {
console.log("bar");
console.log(this);
}
foo(); // calling the function
Note that we are running this in the normal mode, i.e. strict mode is not used.
When running in a browser, the value of this would be ...
setState vs replaceState in React.js
...
Definition by example:
// let's say that this.state is {foo: 42}
this.setState({bar: 117})
// this.state is now {foo: 42, bar: 117}
this.setState({foo: 43})
// this.state is now {foo: 43, bar: 117}
this.replaceState({baz: "hello"})
// this.state. is now {baz: "hello"}
Take...
Is there a way to instantiate a class by name in Java?
...stance() method on this object:
Class<?> clazz = Class.forName("com.foo.MyClass");
Constructor<?> constructor = clazz.getConstructor(String.class, Integer.class);
Object instance = constructor.newInstance("stringparam", 42);
Both methods are known as reflection. You will typically hav...
bodyParser is deprecated express 4
...nded true is that not using extended means that curl --data "user[email]=foo&user[password]=bar" localhost:3000/login would be received by the server in req.body as { user[email]: "foo", ...} whereas req.body would be {user: {email: "foo", ... }} with extended: true.
– ...
How to add/update an attribute to an HTML element using JavaScript?
...nnerHTML slop, I would treat it like one and stick with the e.className = 'fooClass' and e.id = 'fooID'. This is a design preference, but in this instance trying to treat is as anything other than an object works against you.
It will never backfire on you like the other methods might, just be awar...
Double Negation in C++
...ompiler warning. Try this:
int _tmain(int argc, _TCHAR* argv[])
{
int foo = 5;
bool bar = foo;
bool baz = !!foo;
return 0;
}
The 'bar' line generates a "forcing value to bool 'true' or 'false' (performance warning)" on MSVC++, but the 'baz' line sneaks through fine.
...
How to use range-based for() loop with std::map?
... called structured bindings, which allows for the following:
std::map< foo, bar > testing = { /*...blah...*/ };
for ( const auto& [ k, v ] : testing )
{
std::cout << k << "=" << v << "\n";
}
...
Release generating .pdb files, why?
... you can force it to load by specifying the /i option like this .reload /i foo.dll. That will load foo.pdb even if foo.pdb was created after releasing foo.dll.
– Marc Sherman
Nov 29 '12 at 14:20
...
JavaScript plus sign in front of function expression
... functions that are invoked immediately, e.g.:
+function() { console.log("Foo!"); }();
Without the + there, if the parser is in a state where it's expecting a statement (which can be an expression or several non-expression statements), the word function looks like the beginning of a function decl...