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9d70af54e4
Add visits to nodes that already have flat_maps in ast::MutVisitor This PR aims to add `visit_` methods for every node that has a `flat_map_` in MutVisitor, giving implementers free choice over overriding `flat_map` for 1-to-n conversions or `visit` for a 1-to-1. There is one major problem: `flat_map_stmt`. While all other default implementations of `flat_map`s are 1-to-1 conversion, as they either only call visits or a internal 1-to-many conversions are natural, `flat_map_stmt` doesn't follow this pattern. `flat_map_stmt`'s default implementation is a 1-to-n conversion that panics if n > 1 (effectively being a 1-to-[0;1]). This means that it cannot be used as is for a default `visit_stmt`, which would be required to be a 1-to-1. Implementing `visit_stmt` without runtime checks would require it to reach over a potential `flat_map_item` or `filter_map_expr` overrides and call for their `visit` counterparts directly. Other than that, if we want to keep the behavior of `flat_map_stmt` it cannot call `visit_stmt` internally. To me, it seems reasonable to make all default implementations 1-to-1 conversions and let implementers handle `visit_stmt` if they need it, but I don't know if calling `visit` directly when a 1-to-1 is required is ok or not. related to #128974 & #127615 r? ``@petrochenkov`` |
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| .. | ||
| attr | ||
| expand | ||
| util | ||
| ast_traits.rs | ||
| ast.rs | ||
| entry.rs | ||
| format.rs | ||
| lib.rs | ||
| mut_visit.rs | ||
| node_id.rs | ||
| ptr.rs | ||
| token.rs | ||
| tokenstream.rs | ||
| visit.rs | ||