It doesn't as you've already made that decision when adding a property. Almost always you get rid of the property entirely and replace it with a new one (and th

It doesn't as you've already made that decision when adding a property. Almost always you get rid of the property entirely and replace it with a new one (and the type), you extremely rarely change the type. And you will almost always know what type a property needs to be. Name? string. IsActive? boolean. Last modified? Date. Etc. Also typescript just has number, so you're not even faffing around thinking "int, float, long, double, decimal, unsigned, signed" when adding a number. Although this is ultimately a bad thing.