pub fn empty_parameter_environment(self) -> ParameterEnvironment<'tcx> {

        // for an empty parameter environment, there ARE no free
        // regions, so it shouldn't matter what we use for the free id
        let free_id_outlive = self.region_maps.node_extent(ast::DUMMY_NODE_ID);
        ty::ParameterEnvironment {
            free_substs: self.intern_substs(&[]),
            caller_bounds: Vec::new(),
            implicit_region_bound: self.mk_region(ty::ReEmpty),
            free_id_outlive: free_id_outlive,
            is_copy_cache: RefCell::new(FxHashMap()),
            is_sized_cache: RefCell::new(FxHashMap()),
        }
    }
/// Construct a parameter environment suitable for static contexts or other contexts where there
/// are no free type/lifetime parameters in scope.
Construct a parameter environment suitable for static contexts or other contexts where there
are no free type/lifetime parameters in scope.
Construct a parameter environment suitable for static contexts or other contexts where there are no free type / lifetime parameters in scope .
pub fn empty_parameter_environment(self) -> ParameterEnvironment<'tcx> {
        // for an empty parameter environment, there ARE no free
        // regions, so it shouldn't matter what we use for the free id
        let free_id_outlive = self.region_maps.node_extent(ast::DUMMY_NODE_ID);
        ty::ParameterEnvironment {
            free_substs: self.intern_substs(&[]),
            caller_bounds: Vec::new(),
            implicit_region_bound: self.mk_region(ty::ReEmpty),
            free_id_outlive: free_id_outlive,
            is_copy_cache: RefCell::new(FxHashMap()),
            is_sized_cache: RefCell::new(FxHashMap()),
        }
    }
pub fn empty_parameter_environment ( self ) -> ParameterEnvironment < ' tcx > { // for an empty parameter environment, there ARE no free // regions, so it shouldn't matter what we use for the free id let free_id_outlive = self . region_maps . node_extent ( ast :: DUMMY_NODE_ID ) ; ty :: ParameterEnvironment { free_substs : self . intern_substs ( & [ ] ) , caller_bounds : Vec :: new ( ) , implicit_region_bound : self . mk_region ( ty :: ReEmpty ) , free_id_outlive : free_id_outlive , is_copy_cache : RefCell :: new ( FxHashMap ( ) ) , is_sized_cache : RefCell :: new ( FxHashMap ( ) ) , } }
Construct a parameter environment suitable for static contexts or other contexts where there
are no free type/lifetime parameters in scope.
Construct a parameter environment suitable for static contexts or other contexts where there are no free type / lifetime parameters in scope .
self