Okay. Thanks. On Jan 19, 2015 11:32 AM, "Allen Wirfs-Brock" <[email protected]> wrote:
> > On Jan 19, 2015, at 5:32 AM, FabrÃcio Matté wrote: > > Your second example may break if the constructor is called via > `.call()`/`.apply()` or as a *CallExpression : MemberExpression* or if it > has been `.bind()`ed. Although these may look like corner cases, a good > transform should cover these cases, especially *CallExpression : > MemberExpression* as it is very common in Node.js land to have > constructors exported as properties of an exported object. > > > This style of `this` testing is what was necessary to distinguish [[call]] > from [[construct]] under the old ES6 @@create design. And the above edge > cases were what complicated all of the built-in constructors (and required > branding checks and initialization flags) to fully cover. > > It was the complexity of correctly identifying those edge cases which lead > us to recommending that JS code should never try to do it, and JS > developers shouldn't try to defined classes whose constructors did an > implicit 'new' when called. > > With 'new.target' that complexity all goes away and I see no particularly > reason to discourage constructors that 'new' themselves when called as > functions. > > Allen >
_______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
