Ecdsa.recover: def of bend-collections-laws-crypto@1.0.0.0
Import: import bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/ecdsa.bend as Ecdsa
Lines 240-243 of bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/ecdsa.bend: https://jend.leeeet.dev/read.txt?path=bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/ecdsa.bend&start_line=240&end_line=243

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

# the 65-byte uncompressed key recovered from H (32 bytes) and
# r || s || id (65 bytes, id in 0..3)
def recover(+one: Nat, +h: List<&2, U32>, +sig: List<&2, U32>) -> Maybe<&2, List<&2, U32>>:
  recover_len(one, h, sig, Bool.and(CV.length_is(32n, h), CV.length_is(65n, sig)))

Uses (7):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.and
  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=U32
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/curve.bend&name=length_is
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/ecdsa.bend&name=recover_len