use rustc::ty::fold::{TypeFoldable, TypeVisitor};
use rustc::ty::{self, Ty, TyCtxt};
-use rustc::util::nodemap::FxHashSet;
-use syntax::source_map::Span;
+use rustc_data_structures::fx::FxHashSet;
+use rustc_span::source_map::Span;
#[derive(Clone, PartialEq, Eq, Hash, Debug)]
pub struct Parameter(pub u32);