impl'd EqGadget, CondSelectGadget, R1CSVar for Vec<T>

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## Pending
 
+* [\#93](https://github.com/arkworks-rs/r1cs-std/pull/93) Implement `EqGadget`, `CondSelectGadget`, and `R1CSVar` for `Vec<T>`
+
 ### Breaking changes
 
 - [\#86](https://github.com/arkworks-rs/r1cs-std/pull/86) Change the API for domains for coset.

src/eq.rs

@@ -128,3 +128,31 @@ impl<T: EqGadget<F> + R1CSVar<F>, F: Field> EqGadget<F> for [T] {
         }
     }
 }
+
+// EqGadget for Vec<T> just calls down to EqGadget for [T]
+impl<T: EqGadget<F> + R1CSVar<F>, F: Field> EqGadget<F> for Vec<T> {
+    #[tracing::instrument(target = "r1cs", skip(self, other))]
+    fn is_eq(&self, other: &Self) -> Result<Boolean<F>, SynthesisError> {
+        self.as_slice().is_eq(other.as_slice())
+    }
+
+    #[tracing::instrument(target = "r1cs", skip(self, other))]
+    fn conditional_enforce_equal(
+        &self,
+        other: &Self,
+        condition: &Boolean<F>,
+    ) -> Result<(), SynthesisError> {
+        self.as_slice()
+            .conditional_enforce_equal(other.as_slice(), condition)
+    }
+
+    #[tracing::instrument(target = "r1cs", skip(self, other))]
+    fn conditional_enforce_not_equal(
+        &self,
+        other: &Self,
+        should_enforce: &Boolean<F>,
+    ) -> Result<(), SynthesisError> {
+        self.as_slice()
+            .conditional_enforce_not_equal(other.as_slice(), should_enforce)
+    }
+}

src/lib.rs

@@ -124,6 +124,19 @@ impl<'a, F: Field, T: 'a + R1CSVar<F>> R1CSVar<F> for &'a T {
     }
 }
 
+// R1CSVar for Vec<T> just calls down to R1CSVar for [T]
+impl<F: Field, T: R1CSVar<F>> R1CSVar<F> for Vec<T> {
+    type Value = Vec<T::Value>;
+
+    fn cs(&self) -> ark_relations::r1cs::ConstraintSystemRef<F> {
+        self.as_slice().cs()
+    }
+
+    fn value(&self) -> Result<Self::Value, ark_relations::r1cs::SynthesisError> {
+        self.as_slice().value()
+    }
+}
+
 /// A utility trait to convert `Self` to `Result<T, SynthesisErrorA`.>
 pub trait Assignment<T> {
     /// Converts `self` to `Result`.

src/select.rs

@@ -115,3 +115,24 @@ where
         constants: &[Self::TableConstant],
     ) -> Result<Self, SynthesisError>;
 }
+
+impl<ConstraintF, T> CondSelectGadget<ConstraintF> for Vec<T>
+where
+    ConstraintF: Field,
+    T: CondSelectGadget<ConstraintF>,
+{
+    #[tracing::instrument(target = "r1cs", skip(true_value, false_value))]
+    fn conditionally_select(
+        cond: &Boolean<ConstraintF>,
+        true_value: &Vec<T>,
+        false_value: &Vec<T>,
+    ) -> Result<Vec<T>, SynthesisError> {
+        assert_eq!(true_value.len(), false_value.len());
+
+        true_value
+            .iter()
+            .zip(false_value.iter())
+            .map(|(t, f)| T::conditionally_select(cond, t, f))
+            .collect()
+    }
+}