I think they’re nominally typed. Consider this example: type student_t = { age: int; } type worker_t = { age: int; } let new_worker (age: int) : worker_t = {age = age;} let is_adult (student: student_t) : bool = student.age >= 18 I get a type error when I do: let result = is_adult (new_wor…

I don’t know what you mean by “nominally”, but a record-declaration declares these new field-names. Do it again (the identical declaration), and you redeclare the field-names. The new declarations obscure (or “shadow”) the old ones. But code or data that was created using the first declaration wi…

Are OCaml records structurally typed or nominally typed?

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shonfeder July 23, 2023, 5:40am 4

Records are nominally typed, but objects are structurally typed. They are even given as the example on Structural type system - Wikipedia

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Are OCaml records structurally typed or nominally typed?

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