Struct ra_ap_hir::SemanticsScope[][src]

pub struct SemanticsScope<'a> {
    pub db: &'a dyn HirDatabase,
    // some fields omitted
}
Expand description

SemanticScope encapsulates the notion of a scope (the set of visible names) at a particular program point.

It is a bit tricky, as scopes do not really exist inside the compiler. Rather, the compiler directly computes for each reference the definition it refers to. It might transiently compute the explicit scope map while doing so, but, generally, this is not something left after the analysis.

However, we do very much need explicit scopes for IDE purposes – completion, at its core, lists the contents of the current scope. The notion of scope is also useful to answer questions like “what would be the meaning of this piece of code if we inserted it into this position?”.

So SemanticsScope is constructed from a specific program point (a syntax node or just a raw offset) and provides access to the set of visible names on a somewhat best-effort basis.

Note that if you are wondering “what does this specific existing name mean?”, you’d better use the resolve_ family of methods.

Fields

db: &'a dyn HirDatabase

Implementations

Note: FxHashSet<TraitId> should be treated as an opaque type, passed into `Type

Resolve a path as-if it was written at the given scope. This is necessary a heuristic, as it doesn’t take hygiene into account.

Trait Implementations

Formats the value using the given formatter. Read more

Auto Trait Implementations

Blanket Implementations

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Performs the conversion.

Instruments this type with the provided Span, returning an Instrumented wrapper. Read more

Instruments this type with the current Span, returning an Instrumented wrapper. Read more

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.