Proof.sign_if_eq: def of bend-collections-laws-crypto@1.0.0.0
Import: import bend-collections-laws-crypto@1.0.0.0/proofs/crypto/ed25519/proof.bend as Proof
Lines 130-135 of bend-collections-laws-crypto@1.0.0.0/proofs/crypto/ed25519/proof.bend: https://jend.leeeet.dev/read.txt?path=bend-collections-laws-crypto@1.0.0.0/proofs/crypto/ed25519/proof.bend&start_line=130&end_line=135

import Base
import bend-collections-laws-crypto@1.0.0.0/src/crypto/ed25519/ed25519.bend as E
import bend-collections-laws-crypto@1.0.0.0/src/crypto/sign.bend as SG
import bend-collections-laws-crypto@1.0.0.0/proofs/lib/logic.bend as L

def sign_if_eq(+sk: List<&2, U32>, +msg: List<&2, U32>, +ok: Bool, +S: List<&2, U32>, +hok: {ok == True{} : Bool}, +e: {E.sign_raw(sk, msg) == S : List<&2, U32>}) -> {SG.sign_if(sk, msg, ok) == Some{S} : Maybe<&2, List<&2, U32>>}:
  match ok:
    case True{}:
      Equal.cong(List<&2, U32>, Maybe<&2, List<&2, U32>>, z => Some{z}, E.sign_raw(sk, msg), S, e)
    case False{}:
      Empty.absurd({SG.sign_if(sk, msg, False{}) == Some{S} : Maybe<&2, List<&2, U32>>}, L.true_false(Equal.sym(Bool, False{}, True{}, hok)))

Uses (10):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Empty.absurd
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.cong
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.sym
  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=U32
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/proofs/lib/logic.bend&name=true_false
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/src/crypto/ed25519/ed25519.bend&name=sign_raw
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-crypto@1.0.0.0/src/crypto/sign.bend&name=sign_if