Gate docs

Author: pmikolajczyk41

crates/shielder-circuits/src/gates/membership.rs

@@ -31,6 +31,11 @@ impl<F: Field, const N: usize> Gate<F> for MembershipGate<N> {
     type Values = MembershipGateValues<F, N>;
     type Advices = (Column<Advice>, [Column<Advice>; N]);
 
+    /// The gate operates on a single advice column `needle` and `N` advice columns `haystack`. It
+    /// enforces that:
+    ///
+    /// `(needle[x] - haystack_1[x]) · … · (needle[x] - haystack_N[x]) = 0`, where `x` is the row
+    /// where the gate is enabled.
     fn create_gate(
         cs: &mut ConstraintSystem<F>,
         (needle_advice, haystack_advice): Self::Advices,

crates/shielder-circuits/src/gates/range_check.rs

@@ -26,6 +26,13 @@ impl<const CHUNK_SIZE: usize, F: FieldExt> Gate<F> for RangeCheckGate<CHUNK_SIZE
     type Values = RangeCheckGateValues<F>;
     type Advices = Column<Advice>;
 
+    /// The gate operates on a single advice column `A` and a table `T`. It enforces that:
+    ///
+    /// `A[x] - A[x+1] * 2^CHUNK_SIZE` belongs to `T`
+    ///
+    /// where:
+    ///  - `x` is the row where the gate is enabled
+    ///  - `T` represents set `[0, 2^CHUNK_SIZE)`
     fn create_gate(cs: &mut ConstraintSystem<F>, running_sum: Self::Advices) -> Self {
         let selector = cs.complex_selector();
         let table = RangeTable::new(cs);

crates/shielder-circuits/src/gates/sum.rs

@@ -31,6 +31,8 @@ impl<F: Field> Gate<F> for SumGate {
     type Values = SumGateValues<F>;
     type Advices = [Column<Advice>; 3];
 
+    /// The gate operates on three advice columns `A`, `B`, and `C`. It enforces that:
+    /// `A[x] + B[x] = C[x]`, where `x` is the row where the gate is enabled.
     fn create_gate(cs: &mut ConstraintSystem<F>, advice: Self::Advices) -> Self {
         Self::ensure_unique_columns(&advice);
         let selector = cs.selector();