domenic at domenicdenicola.com (2013-11-12T18:54:22.212Z)
On Nov 1, 2013, at 1:11 PM, Mark S. Miller wrote:
> For the ES6 builtin types, I have no idea.
>
Most branded ES6 built-ins have non-destructive brand-checking methods that call be used to perform brand checks.
For example,
```js
function isMap(obj) {
try {Map.prototype.size.call(obj); return true} catch (e) {return false}
}
```
On Nov 1, 2013, at 1:11 PM, Mark S. Miller wrote: > For the ES6 builtin types, I have no idea. > Most branded ES6 built-ins have non-destructive brand-checking methods that call be used to perform brand checks. For example, function isMap(obj) { try {Map.prototype.size.call(obj); return true} catch (e) {return false} }