Lamdu now elaborates on non-trivial type errors! In the screenshot several type errors are demonstrated: • A simple one: Text isn’t Num • “Occurs check”:

func func

means that the type of

func

is infinitely

(((a -> a) -> a) -> a) -> …

(note it can be done if wrapping in a nominal type to break the loop • Expand-record when inside record has the same fields. The message here isn’t yet very informative to which field is duplicated. Just says “constraints” for now • Scoped type variable escape (i.e “skolem”) error. This is equivalent to leaking Haskell’s

ST

monad’s

s

variable