PreparedCommitment & PreparedVerifierKey don't belong on `Polynom…

…ialCommitment` trait (#127)

* PreparedCommitment was never used

* Remove PreparedVerifierKey

* place `Prepared` types on `PCCheckVar` trait

src/constraints.rs

@@ -1,6 +1,6 @@
 use crate::{
     data_structures::LabeledCommitment, BatchLCProof, LCTerm, LinearCombination,
-    PolynomialCommitment, String, Vec,
+    PCPreparedCommitment, PCPreparedVerifierKey, PolynomialCommitment, String, Vec,
 };
 use ark_crypto_primitives::sponge::CryptographicSponge;
 use ark_ff::PrimeField;
@@ -99,16 +99,20 @@ pub trait PCCheckVar<
     S: CryptographicSponge,
 >: Clone
 {
+    /// The prepared verifier key for the scheme; used to check an evaluation proof.
+    type PreparedVerifierKey: PCPreparedVerifierKey<PC::VerifierKey> + Clone;
+    /// The prepared commitment to a polynomial.
+    type PreparedCommitment: PCPreparedCommitment<PC::Commitment>;
     /// An allocated version of `PC::VerifierKey`.
     type VerifierKeyVar: AllocVar<PC::VerifierKey, ConstraintF> + Clone;
     /// An allocated version of `PC::PreparedVerifierKey`.
-    type PreparedVerifierKeyVar: AllocVar<PC::PreparedVerifierKey, ConstraintF>
+    type PreparedVerifierKeyVar: AllocVar<Self::PreparedVerifierKey, ConstraintF>
         + Clone
         + PrepareGadget<Self::VerifierKeyVar, ConstraintF>;
     /// An allocated version of `PC::Commitment`.
     type CommitmentVar: AllocVar<PC::Commitment, ConstraintF> + Clone;
     /// An allocated version of `PC::PreparedCommitment`.
-    type PreparedCommitmentVar: AllocVar<PC::PreparedCommitment, ConstraintF>
+    type PreparedCommitmentVar: AllocVar<Self::PreparedCommitment, ConstraintF>
         + PrepareGadget<Self::CommitmentVar, ConstraintF>
         + Clone;
     /// An allocated version of `LabeledCommitment<PC::Commitment>`.

src/ipa_pc/mod.rs

@@ -346,9 +346,7 @@ where
     type UniversalParams = UniversalParams<G>;
     type CommitterKey = CommitterKey<G>;
     type VerifierKey = VerifierKey<G>;
-    type PreparedVerifierKey = PreparedVerifierKey<G>;
     type Commitment = Commitment<G>;
-    type PreparedCommitment = PreparedCommitment<G>;
     type Randomness = Randomness<G>;
     type Proof = Proof<G>;
     type BatchProof = Vec<Self::Proof>;

src/lib.rs

@@ -154,12 +154,8 @@ pub trait PolynomialCommitment<F: PrimeField, P: Polynomial<F>, S: Cryptographic
     type CommitterKey: PCCommitterKey;
     /// The verifier key for the scheme; used to check an evaluation proof.
     type VerifierKey: PCVerifierKey;
-    /// The prepared verifier key for the scheme; used to check an evaluation proof.
-    type PreparedVerifierKey: PCPreparedVerifierKey<Self::VerifierKey> + Clone;
     /// The commitment to a polynomial.
     type Commitment: PCCommitment + Default;
-    /// The prepared commitment to a polynomial.
-    type PreparedCommitment: PCPreparedCommitment<Self::Commitment>;
     /// The commitment randomness.
     type Randomness: PCRandomness;
     /// The evaluation proof for a single point.

src/marlin/marlin_pc/mod.rs

@@ -65,9 +65,7 @@ where
     type UniversalParams = UniversalParams<E>;
     type CommitterKey = CommitterKey<E>;
     type VerifierKey = VerifierKey<E>;
-    type PreparedVerifierKey = PreparedVerifierKey<E>;
     type Commitment = Commitment<E>;
-    type PreparedCommitment = PreparedCommitment<E>;
     type Randomness = Randomness<E::ScalarField, P>;
     type Proof = kzg10::Proof<E>;
     type BatchProof = Vec<Self::Proof>;

src/marlin/marlin_pst13_pc/mod.rs

@@ -150,9 +150,7 @@ where
     type UniversalParams = UniversalParams<E, P>;
     type CommitterKey = CommitterKey<E, P>;
     type VerifierKey = VerifierKey<E>;
-    type PreparedVerifierKey = PreparedVerifierKey<E>;
     type Commitment = marlin_pc::Commitment<E>;
-    type PreparedCommitment = marlin_pc::PreparedCommitment<E>;
     type Randomness = Randomness<E, P>;
     type Proof = Proof<E>;
     type BatchProof = Vec<Self::Proof>;

src/marlin/mod.rs

@@ -239,7 +239,6 @@ where
             P,
             S,
             Commitment = marlin_pc::Commitment<E>,
-            PreparedCommitment = marlin_pc::PreparedCommitment<E>,
             Error = Error,
         >,
         PC::Randomness: 'a + AddAssign<(E::ScalarField, &'a PC::Randomness)>,
@@ -336,7 +335,6 @@ where
             P,
             S,
             Commitment = marlin_pc::Commitment<E>,
-            PreparedCommitment = marlin_pc::PreparedCommitment<E>,
             Error = Error,
         >,
         PC::Commitment: 'a,

src/sonic_pc/mod.rs

@@ -145,9 +145,7 @@ where
     type UniversalParams = UniversalParams<E>;
     type CommitterKey = CommitterKey<E>;
     type VerifierKey = VerifierKey<E>;
-    type PreparedVerifierKey = PreparedVerifierKey<E>;
     type Commitment = Commitment<E>;
-    type PreparedCommitment = PreparedCommitment<E>;
     type Randomness = Randomness<E::ScalarField, P>;
     type Proof = kzg10::Proof<E>;
     type BatchProof = Vec<Self::Proof>;