Module rustc_resolve::late::lifetimes

Resolution of early vs late bound lifetimes.

Name resolution for lifetimes is performed on the AST and embedded into HIR. From this information, typechecking needs to transform the lifetime parameters into bound lifetimes. Lifetimes can be early-bound or late-bound. Construction of typechecking terms needs to visit the types in HIR to identify late-bound lifetimes and assign their Debruijn indices. This file is also responsible for assigning their semantics to implicit lifetimes in trait objects.

Structs

LifetimeContext 🔒

NamedRegionMap 🔒

Maps the id of each lifetime reference to the lifetime decl that it corresponds to.

TruncatedScopeDebug 🔒

Enums

BinderScopeType 🔒

Scope 🔒

Constants

ROOT_SCOPE 🔒

Traits

RegionExt 🔒

Functions

compute_object_lifetime_defaults 🔒

convert_named_region_map 🔒

do_resolve 🔒

is_late_bound_map 🔒

Detects late-bound lifetimes and inserts them into late_bound.

item_for 🔒

Finds the Item that contains the given LocalDefId

late_region_as_bound_region 🔒

object_lifetime_defaults_for_item 🔒

Scan the bounds and where-clauses on parameters to extract bounds of the form T:'a so as to determine the ObjectLifetimeDefault for each type parameter.

provide

resolve_lifetimes 🔒

Computes the ResolveLifetimes map that contains data for an entire Item. You should not read the result of this query directly, but rather use named_region_map, is_late_bound_map, etc.

resolve_lifetimes_for 🔒

Given any owner (structs, traits, trait methods, etc.), does lifetime resolution. There are two important things this does. First, we have to resolve lifetimes for the entire Item that contains this owner, because that’s the largest “scope” where we can have relevant lifetimes. Second, if we are asking for lifetimes in a trait definition, we use resolve_lifetimes_trait_definition instead of resolve_lifetimes, which does not descend into the trait items and does not emit diagnostics. This allows us to avoid cycles. Importantly, if we ask for lifetimes for lifetimes that have an owner other than the trait itself (like the trait methods or associated types), then we just use the regular resolve_lifetimes.

resolve_lifetimes_trait_definition 🔒

Like resolve_lifetimes, but does not resolve lifetimes for trait items. Also does not generate any diagnostics.

sub_items_have_self_param 🔒

In traits, there is an implicit Self type parameter which comes before the generics. We have to account for this when computing the index of the other generic parameters. This function returns whether there is such an implicit parameter defined on the given item.

Type Definitions

ScopeRef 🔒