liveness_map: &'me NllLivenessMap,
/// Head of a linked list of **definitions** of each variable --
- /// definition in this context means assignment, e.g. `x` is
+ /// definition in this context means assignment, e.g., `x` is
/// defined in `x = y` but not `y`; that first def is the head of
/// a linked list that lets you enumerate all places the variable
/// is assigned.