Ecdsa.recover_x_if: def of bend-collections@1.0.0.0
Import: import bend-collections@1.0.0.0/spec/crypto/secp256k1/ecdsa.bend as Ecdsa
Lines 215-220 of bend-collections@1.0.0.0/spec/crypto/secp256k1/ecdsa.bend: https://jend.leeeet.dev/read.txt?path=bend-collections@1.0.0.0/spec/crypto/secp256k1/ecdsa.bend&start_line=215&end_line=220

import Base
import bend-collections@1.0.0.0/spec/crypto/secp256k1/curve.bend as CV

# R: the point of x-coordinate x = r + j n (j = id / 2, x < p) whose y has
# parity id mod 2
def recover_x_if(+one: Nat, +e: Nat, +r: Nat, +s: Nat, +id: Nat, +x: Nat, ok: Bool) -> Maybe<&2, List<&2, U32>>:
  match ok:
    case True{}: recover_r(one, e, r, s, CV.decompress(p(one), x, Nat.mod(id, 2n)))
    case False{}: None{}

Uses (9):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.mod
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=bend-collections@1.0.0.0/spec/crypto/secp256k1/curve.bend&name=decompress
  https://jend.leeeet.dev/definition.txt?path=bend-collections@1.0.0.0/spec/crypto/secp256k1/ecdsa.bend&name=p
  https://jend.leeeet.dev/definition.txt?path=bend-collections@1.0.0.0/spec/crypto/secp256k1/ecdsa.bend&name=recover_r