Switch to new <V:Visitor> visitor (rather than @Visitor).

Alpha-renamed top-level visit_* functions to walk_*.
(Motivation: Distinguish visit action and recursive traversal.)

Abstract over `&mut self` rather than over `@mut self`.

This required some acrobatics, notably the

  `impl<E> Visitor<E> for @mut Visitor<E>`

and corresponding introduction of `@mut Visitor` and some local `let
mut` bindings.

Remove oldvisit reference.

Added default implementations for all of the Visitor trait methods.

Note that both `visit_expr_post` and `visit_ty` are no-op's by
default, just like they are in `oldvisit::default_visitor`.

Refactoring: extract logic to ease swapping visit for oldvisit (hopefully).

0 files changed, 0 insertions, 0 deletions