Module rustc::ty::wf [−] [src]

🔬 This is a nightly-only experimental API. (rustc_private)

Enums

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Experimental

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Implied bounds are region relationships that we deduce automatically. The idea is that (e.g.) a caller must check that a function's argument types are well-formed immediately before calling that fn, and hence the callee can assume that its argument types are well-formed. This may imply certain relationships between generic parameters. For example:

Functions

implied_bounds	[ Experimental ] Compute the implied bounds that a callee/impl can assume based on the fact that caller/projector has ensured that `ty` is WF. See the `ImpliedBound` type for more details.
object_region_bounds	[ Experimental ] Given an object type like `SomeTrait+Send`, computes the lifetime bounds that must hold on the elided self type. These are derived from the declarations of `SomeTrait`, `Send`, and friends -- if they declare `trait SomeTrait : 'static`, for example, then `'static` would appear in the list. The hard work is done by `ty::required_region_bounds`, see that for more information.
obligations	[ Experimental ] Returns the set of obligations needed to make `ty` well-formed. If `ty` contains unresolved inference variables, this may include further WF obligations. However, if `ty` IS an unresolved inference variable, returns `None`, because we are not able to make any progress at all. This is to prevent "livelock" where we say "$0 is WF if $0 is WF".
predicate_obligations	[ Experimental ]
trait_obligations	[ Experimental ] Returns the obligations that make this trait reference well-formed. For example, if there is a trait `Set` defined like `trait Set<K:Eq>`, then the trait reference `Foo: Set<Bar>` is WF if `Bar: Eq`.