src/librustc_infer/infer/outlives/mod.rs

   1 //! Various code related to computing outlives relations.
   2
   3 pub mod env;
   4 pub mod obligations;
   5 pub mod verify;
   6
   7 use rustc::traits::query::OutlivesBound;
   8 use rustc::ty;
   9
  10 pub fn explicit_outlives_bounds<'tcx>(
  11     param_env: ty::ParamEnv<'tcx>,
  12 ) -> impl Iterator<Item = OutlivesBound<'tcx>> + 'tcx {
  13     debug!("explicit_outlives_bounds()");
  14     param_env.caller_bounds.into_iter().filter_map(move |predicate| match predicate {
  15         ty::Predicate::Projection(..)
  16         | ty::Predicate::Trait(..)
  17         | ty::Predicate::Subtype(..)
  18         | ty::Predicate::WellFormed(..)
  19         | ty::Predicate::ObjectSafe(..)
  20         | ty::Predicate::ClosureKind(..)
  21         | ty::Predicate::TypeOutlives(..)
  22         | ty::Predicate::ConstEvaluatable(..) => None,
  23         ty::Predicate::RegionOutlives(ref data) => data
  24             .no_bound_vars()
  25             .map(|ty::OutlivesPredicate(r_a, r_b)| OutlivesBound::RegionSubRegion(r_b, r_a)),
  26     })
  27 }