You can use Boolean(value) but it will return an 'object' of a 'boolean' type, rather than a primitive boolean (it's one of JS's flaws so is generally avoided).

Note: their example of a similar piece of code is not identical, as it won't cast values like null to false. I think the best example of a clear equivalent would be:

    value = value ? true : false;

The !! mentioned in the article does exactly that.