message: Sprinkle some doc-comments
diff: @@ -252,6 +252,7 @@ pub enum LookupPattern {
  }
  impl LookupPattern {
  + /// Returns the maximum number of lookups per row that are used by the pattern.
  pub fn max_lookups_per_row(&self) -> usize {
  match self {
  LookupPattern::ChaCha => 4,
  @@ -260,6 +261,7 @@ impl LookupPattern {
  }
  }
  + /// Returns the maximum number of values that are used in any vector lookup in this pattern.
  pub fn max_joint_size(&self) -> u32 {
  match self {
  LookupPattern::ChaCha => 3,
  @@ -268,6 +270,7 @@ impl LookupPattern {
  }
  }
  + /// Returns the layout of the lookups used by this pattern.
  pub fn lookups<F: Field>(&self) -> Vec<JointLookupSpec<F>> {
  let curr_row = |column| LocalPosition {
  row: CurrOrNext::Curr,
  @@ -339,6 +342,7 @@ impl LookupPattern {
  }
  }
  + /// Returns the lookup table used by the pattern, or `None` if no specific table is rqeuired.
  pub fn table(&self) -> Option<GateLookupTable> {
  match self {
  LookupPattern::ChaCha | LookupPattern::ChaChaFinal => Some(GateLookupTable::Xor),
  @@ -346,6 +350,8 @@ impl LookupPattern {
  }
  }
  + /// Returns the index of the lookup pattern in the vector of all lookup patterns.
  + // TODO: Delete this (done in dependent PR #584).
  fn to_index(&self) -> usize {
  match self {
  LookupPattern::ChaCha => 0,
  @@ -354,6 +360,7 @@ impl LookupPattern {
  }
  }
  + /// Returns the lookup pattern used by a [GateType] on a given row (current or next).
  pub fn from_gate(gate_type: GateType, curr_or_next: CurrOrNext) -> Option<Self> {
  use CurrOrNext::*;
  use GateType::*;
  