rust/compiler/rustc_ast
Nicholas Nethercote ba1751a201 Avoid more MetaItem-to-Attribute conversions.
There is code for converting `Attribute` (syntactic) to `MetaItem`
(semantic). There is also code for the reverse direction. The reverse
direction isn't really necessary; it's currently only used when
generating attributes, e.g. in `derive` code.

This commit adds some new functions for creating `Attributes`s directly,
without involving `MetaItem`s: `mk_attr_word`, `mk_attr_name_value_str`,
`mk_attr_nested_word`, and
`ExtCtxt::attr_{word,name_value_str,nested_word}`.

These new methods replace the old functions for creating `Attribute`s:
`mk_attr_inner`, `mk_attr_outer`, and `ExtCtxt::attribute`. Those
functions took `MetaItem`s as input, and relied on many other functions
that created `MetaItems`, which are also removed: `mk_name_value_item`,
`mk_list_item`, `mk_word_item`, `mk_nested_word_item`,
`{MetaItem,MetaItemKind,NestedMetaItem}::token_trees`,
`MetaItemKind::attr_args`, `MetaItemLit::{from_lit_kind,to_token}`,
`ExtCtxt::meta_word`.

Overall this cuts more than 100 lines of code and makes thing simpler.
2022-11-29 18:43:53 +11:00
..
src Avoid more MetaItem-to-Attribute conversions. 2022-11-29 18:43:53 +11:00
Cargo.toml rustdoc: use ThinVec for cleaned generics 2022-11-02 16:17:22 -07:00
README.md docs(rustc_ast): update crate descriptions 2021-11-02 21:11:17 -05:00

The rustc_ast crate contains those things concerned purely with syntax that is, the AST ("abstract syntax tree"), along with some definitions for tokens and token streams, data structures/traits for mutating ASTs, and shared definitions for other AST-related parts of the compiler (like the lexer and macro-expansion).

For more information about how these things work in rustc, see the rustc dev guide: