compiler/rustc_middle/src/hir/nested_filter.rs

   1 use rustc_hir::intravisit::nested_filter::NestedFilter;
   2
   3 /// Do not visit nested item-like things, but visit nested things
   4 /// that are inside of an item-like.
   5 ///
   6 /// Notably, possible occurrences of bodies in non-item-like things
   7 /// include: closures/generators, inline `const {}` blocks, and
   8 /// constant arguments of types, e.g. in `let _: [(); /* HERE */];`.
   9 ///
  10 /// **This is the most common choice.** A very common pattern is
  11 /// to use `deep_visit_all_item_likes()` as an outer loop,
  12 /// and to have the visitor that visits the contents of each item
  13 /// using this setting.
  14 pub struct OnlyBodies(());
  15 impl<'hir> NestedFilter<'hir> for OnlyBodies {
  16     type Map = crate::hir::map::Map<'hir>;
  17     const INTER: bool = false;
  18     const INTRA: bool = true;
  19 }
  20
  21 /// Visits all nested things, including item-likes.
  22 ///
  23 /// **This is an unusual choice.** It is used when you want to
  24 /// process everything within their lexical context. Typically you
  25 /// kick off the visit by doing `walk_krate()`.
  26 pub struct All(());
  27 impl<'hir> NestedFilter<'hir> for All {
  28     type Map = crate::hir::map::Map<'hir>;
  29     const INTER: bool = true;
  30     const INTRA: bool = true;
  31 }