Javascript does have structs, it calls them objects.
replyIf I parsed an emailAddress the thing that came out it would look like {'domain':'example.com', 'user':'john-doe'} or emailaddr.domain emailaddr.user and a emailaddr.address method if you like that form. Even if what I parsed ended up as a single string-like field, I would still name that field. emailaddr.address
Salutes for the bit on hiding the constructor, that makes a lot of sense.
It probably does not help anything that in my one attempt at making a javascript web application I did not bother trying to understand how javascript likes it's objects and just forced a python looking model onto it. If any of the web development team saw my code I would definitely get laughed out of the club.
Yeah, in your example the structure is sufficiently dissimilar to a string for TypeScript not to confuse them for each other. However, if you also have an identity provider returning UserInfo objects in the form of {'domain':'example.com', 'user':'john-doe'}, you might not like it that now any email address is a valid UserInfo object. On the type level in TS, you cannot tell those types apart. But I guess you figured that out already.
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