Kind/book/String.unpar.kind2
2024-03-01 20:40:31 -03:00

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String.unpar
: ∀(fst: Char) ∀(lst: Char) ∀(str: String) String
= λfst λlst λstr
let P = λx String
let cons = λhead λtail
let P = λx ∀(head: Char) ∀(tail: String) String
let true = λhead λtail (String.begin tail)
let false = λhead λtail (String.cons head tail)
(~(Char.equal head fst) P true false head tail)
let nil = String.nil
(~str P cons nil)