Use Object.entries

[monolithed]

        for (const prop in e) {
            if (hasOwnProperty(e, prop)) {
                result.push(prop);
            }
        }

        for (const [prop, value] of Object.entries(e)) {
                result.push(prop);
        }

I believe the second example looks more elegant

[dphilipson]

Hi monolithed,

Unfortunately Object.entries() is not supported in all major browsers. In particular, it is absent from Safari on iOS and from Internet Explorer, according to MDN's page on Object.entries().

Actually though, your mentioning this made me realize that it should be using Object.keys() instead, so I'll make that change when I have the chance. Thank you!

[monolithed]

I believe people know about polyfils.

[dphilipson]

Consumers shouldn't need to install a polyfill to use a 40 line library.

[dphilipson]

Alright, should be fixed. The new version simply says

return Object.keys(e) as Array<keyof T>;