It seems possible to nest a class in a constructor which can then be instantiated from anywhere within the class, is this official?
[EDIT] E.g.,
class C {
constructor() {
class D {
constructor() { }
}
}
method() {
var a = new D(); // works fine
}
}
//var a = new D(); // fails in outer scope
The traceur generated JS https://google.github.io/traceur-compiler/demo/repl.html
$traceurRuntime.ModuleStore.getAnonymousModule(function() {
"use strict";
var C = function C() {
var D = function D() {};
($traceurRuntime.createClass)(D, {}, {});
};
($traceurRuntime.createClass)(C, {method: function() {
var a = new D();
}}, {});
return {};
});
//# sourceURL=traceured.js
No, there are no nested classes in ES6, and there is no such thing as private members in the class syntax anyway if you mean that.
Of course you can put a second class as a static property on another class, like this:
class A {
…
}
A.B = class {
…
};
or you use an extra scope:
var C;
{
class D {
constructor() { }
}
C = class C {
constructor() { }
method() {
var a = new D(); // works fine
}
}
}
(There seems to be a bug with traceur as it uses a hoisted var
for the class declaration instead of block scope)
With the proposed class field syntax, it will also be possible to write a single expression or declaration:
class A {
…
static B = class {
…
}
};