----------------------
go_nonrec subst b (Type ty') body
| isTyVar b = go (extendTvSubst subst b ty') body
+ -- let a::* = TYPE ty in <body>
go_nonrec subst b r' body
- | isId b
+ | isId b -- let x = e in <body>
, exprIsTrivial r' || safe_to_inline (idOccInfo b)
= go (extendIdSubst subst b r') body
go_nonrec subst b r' body