Statement.ForIn
type ('M, 'T) t = {
left : ('M, 'T) left;
right : ('M, 'T) Expression.t;
body : ('M, 'T) Statement.t;
each : bool;
comments : ('M, unit) Syntax.t option;
}
and ('M, 'T) left =
| LeftDeclaration of 'M * ('M, 'T) VariableDeclaration.t
| LeftPattern of ('M, 'T) Pattern.t