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What are the differences between JSON and JavaScript object? [duplicate]
...al notation, but there are differences between them.
For example, in JSON all keys must be quoted, while in object literals this is not necessary:
// JSON:
{ "foo": "bar" }
// Object literal:
var o = { foo: "bar" };
The quotes are mandatory on JSON because in JavaScript (more exactly in ECMAScr...
get path for my .exe [duplicate]
... That's not really correct answer. It will give you a string like "file://foo"
– dyatchenko
Dec 4 '15 at 23:43
Also i...
What does enumerable mean?
...his condition is in place because objects have many more properties, especially from inheritance:
console.log(Object.getOwnPropertyNames(Object.prototype));
// ["constructor", "toString", "toLocaleString", "valueOf", "hasOwnProperty", "isPrototypeOf", "propertyIsEnumerable", /* etc. */]
Each of t...
What does jQuery.fn mean?
...roperty.
The jQuery identifier (or $) is just a constructor function, and all instances created with it, inherit from the constructor's prototype.
A simple constructor function:
function Test() {
this.a = 'a';
}
Test.prototype.b = 'b';
var test = new Test();
test.a; // "a", own property
test....
Why is null an object and what's the difference between null and undefined?
...nown what the value is.
One thing to remember is that null is not, conceptually, the same as false or "" or such, even if they equate after type casting, i.e.
name = false;
You: What is name?
JavaScript: Boolean false.
name = '';
You: What is name?
JavaScript: Empty string
*: name in this context...
Curious null-coalescing operator custom implicit conversion behaviour
...l; there's no need to check it for null a second time just because we are calling a lifted conversion operator". We'd them optimize it away to just
new int?(op_Implicit(temp2.Value))
My guess is that we are somewhere caching the fact that the optimized form of (int?)Foo() is new int?(op_implici...
Interface type check with Typescript
...
And if the interface has 100 members, you need to check all 100? Foobar.
– Jenny O'Reilly
Nov 24 '17 at 10:43
6
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Undefined reference to static constexpr char[]
...he same semantics as a function declared inline: it can be defined, identically, in
multiple translation units, must be defined in every translation unit in which it is odr-used, and
the behavior of the program is as if there is exactly one variable.
and modified [basic.def]p2:
A declar...
How do I print the type or class of a variable in Swift?
...lf and any instance using .dynamicType:
struct Box<T> {}
toString("foo".dynamicType) // Swift.String
toString([1, 23, 456].dynamicType) // Swift.Array<Swift.Int>
toString((7 as NSNumber).dynamicType) // __NSCFNumber
toString((Bool?).self) // Swift.Optio...
asp.net mvc: why is Html.CheckBox generating an additional hidden input
...uffinMan: This is not silly option. Lets say your view model has property called IsActive, which is initiated to true in constructor. User deselects checkbox, but since value is not sent to server, model binder doesn't pick it up, and property value is not changed. Model binder shouldn't assume, tha...