fn get_mut_span_in_struct_field<'tcx>(
    tcx: TyCtxt<'tcx>,
    ty: Ty<'tcx>,
    field: FieldIdx,
) -> Option<Span>
Expand description

Given a field that needs to be mutable, returns a span where the “ mut “ could go. This function expects the local to be a reference to a struct in order to produce a span.

LL |     s: &'a   String
   |           ^^^ returns a span taking up the space here