Comment by RichieAHB

One thing I’ve never found a name for (and, as a result, a good way to reference to people) is Typescript’s interesting behaviour around the Erased Structural Types mentioned here: https://github.com/gibbok/typescript-book#erased-structural-....

Objects passed to a function that accepts an object type can generally have more properties that needed given Typescript’s structural typing. That is unless you pass a literal directly to the function (I.e. inline the obj variable in the linked example). In which case Typescript will complain about the excess properties. Ergonomic but confusing the first time you come across it.