def drop_len_le

bend-collections-laws-crypto@1.0.0.0 · proofs/crypto/curve25519/poly.bend:357

import Base
import bend-collections-laws-crypto@1.0.0.0/src/crypto/curve25519/field.bend as F

357def drop_len_le(+n: Nat, +k: Nat, +xs: List<&2, U32>, +hl: {len_le(Nat.add(n, k), xs) == True{} : Bool}) -> {len_le(k, F.drop(n, xs)) == True{} : Bool}:
358  match n xs:
359    case 0n _:
360      hl
361    case 1n+m Nil{}:
362      len_le_nil(k)
363    case 1n+ +m Con{x, +xt}:
364      drop_len_le(m, k, xt, hl)