add is_trait(DefId) helper to TyCtxt

Co-authored-by: Tyler Mandry <tmandry@gmail.com>
This commit is contained in:
Niko Matsakis 2018-07-02 10:34:19 -04:00
parent 7bbbed9046
commit 327093007a

View File

@ -518,10 +518,25 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
result
}
/// True if `def_id` refers to a closure (e.g., `|x| x * 2`). Note
/// that closures have a def-id, but the closure *expression* also
/// has a `HirId` that is located within the context where the
/// closure appears (and, sadly, a corresponding `NodeId`, since
/// those are not yet phased out). The parent of the closure's
/// def-id will also be the context where it appears.
pub fn is_closure(self, def_id: DefId) -> bool {
self.def_key(def_id).disambiguated_data.data == DefPathData::ClosureExpr
}
/// True if `def_id` refers to a trait (e.g., `trait Foo { ... }`).
pub fn is_trait(self, def_id: DefId) -> bool {
if let DefPathData::Trait(_) = self.def_key(def_id).disambiguated_data.data {
true
} else {
false
}
}
/// True if this def-id refers to the implicit constructor for
/// a tuple struct like `struct Foo(u32)`.
pub fn is_struct_constructor(self, def_id: DefId) -> bool {