message: Fixed some commenting
diff: // a2 = a2p0a2p1a2p2a2p3a2c0a2c1a2c2a2c3a2c4a2c5a2c6a2c7a2c8a2c9a2c10a2c11a2c12a2c13a2c14a2c15a2c16a2c17a2c18a2c19
  //
  // where
  -// * aXpi is a 12-bit sub-limb of limb aX
  +// * aXpi is a 12-bit sublimb of limb aX
  // * aXci is a 2-bit "crumb" limb of aX
  //
  // Input structure:
  // (*) Row offsets
  // (**) Some part of the limb is contained in this row
  //
  -// Constraints
  +// Constraints:
  //
  // For efficiency, the foreign field element inputs are constrained
  -// by their sub-limbs according to their type.
  -// * 12-bit sub-limbs are constrainted with plookups
  +// by their sublimbs according to their type.
  +// * 12-bit sublimbs are constrainted with plookups
  // * 2-bit crumbs are constrained with degree-4 constraints
  //
  -// Example
  +// Example:
  //
  // This example shows how input a is constrained
  //
  // The 12-bit chunks are constrained with plookups and the 2-bit crumbs constrained with
  // degree-4 constraints of the form x*(x - 1)*(x - 2)*(x - 3)
  //
  -// Gate types
  +// Gate types:
  //
  // Each unique row structure corresponds to a unique foreign mul CircuitGate type
  //
  // 6 ForeignMul1 "
  // 7 ForeignMul1 "
  //
  -// Nb. each circuitgate type corresponds to a unique polynomial and thus
  +// Nb. each CircuitGate type corresponds to a unique polynomial and thus
  // is assigned its own unique powers of alpha
  use crate::expr::{Column, E};
  