diff options
Diffstat (limited to 'compiler/rustc_ast/src/tokenstream.rs')
| -rw-r--r-- | compiler/rustc_ast/src/tokenstream.rs | 62 |
1 files changed, 1 insertions, 61 deletions
diff --git a/compiler/rustc_ast/src/tokenstream.rs b/compiler/rustc_ast/src/tokenstream.rs index fb331e74aeb..43d25d18075 100644 --- a/compiler/rustc_ast/src/tokenstream.rs +++ b/compiler/rustc_ast/src/tokenstream.rs @@ -25,7 +25,7 @@ use rustc_span::{DUMMY_SP, Span, SpanDecoder, SpanEncoder, Symbol, sym}; use crate::ast::AttrStyle; use crate::ast_traits::{HasAttrs, HasTokens}; -use crate::token::{self, Delimiter, InvisibleOrigin, Nonterminal, Token, TokenKind}; +use crate::token::{self, Delimiter, Token, TokenKind}; use crate::{AttrVec, Attribute}; /// Part of a `TokenStream`. @@ -305,11 +305,6 @@ pub struct AttrsTarget { } /// A `TokenStream` is an abstract sequence of tokens, organized into [`TokenTree`]s. -/// -/// The goal is for procedural macros to work with `TokenStream`s and `TokenTree`s -/// instead of a representation of the abstract syntax tree. -/// Today's `TokenTree`s can still contain AST via `token::Interpolated` for -/// backwards compatibility. #[derive(Clone, Debug, Default, Encodable, Decodable)] pub struct TokenStream(pub(crate) Arc<Vec<TokenTree>>); @@ -476,61 +471,6 @@ impl TokenStream { TokenStream::new(tts) } - pub fn from_nonterminal_ast(nt: &Nonterminal) -> TokenStream { - match nt { - Nonterminal::NtBlock(block) => TokenStream::from_ast(block), - } - } - - fn flatten_token(token: &Token, spacing: Spacing) -> TokenTree { - match token.kind { - token::NtIdent(ident, is_raw) => { - TokenTree::Token(Token::new(token::Ident(ident.name, is_raw), ident.span), spacing) - } - token::NtLifetime(ident, is_raw) => TokenTree::Delimited( - DelimSpan::from_single(token.span), - DelimSpacing::new(Spacing::JointHidden, spacing), - Delimiter::Invisible(InvisibleOrigin::FlattenToken), - TokenStream::token_alone(token::Lifetime(ident.name, is_raw), ident.span), - ), - token::Interpolated(ref nt) => TokenTree::Delimited( - DelimSpan::from_single(token.span), - DelimSpacing::new(Spacing::JointHidden, spacing), - Delimiter::Invisible(InvisibleOrigin::FlattenToken), - TokenStream::from_nonterminal_ast(&nt).flattened(), - ), - _ => TokenTree::Token(token.clone(), spacing), - } - } - - fn flatten_token_tree(tree: &TokenTree) -> TokenTree { - match tree { - TokenTree::Token(token, spacing) => TokenStream::flatten_token(token, *spacing), - TokenTree::Delimited(span, spacing, delim, tts) => { - TokenTree::Delimited(*span, *spacing, *delim, tts.flattened()) - } - } - } - - #[must_use] - pub fn flattened(&self) -> TokenStream { - fn can_skip(stream: &TokenStream) -> bool { - stream.iter().all(|tree| match tree { - TokenTree::Token(token, _) => !matches!( - token.kind, - token::NtIdent(..) | token::NtLifetime(..) | token::Interpolated(..) - ), - TokenTree::Delimited(.., inner) => can_skip(inner), - }) - } - - if can_skip(self) { - return self.clone(); - } - - self.iter().map(|tree| TokenStream::flatten_token_tree(tree)).collect() - } - // If `vec` is not empty, try to glue `tt` onto its last token. The return // value indicates if gluing took place. fn try_glue_to_last(vec: &mut Vec<TokenTree>, tt: &TokenTree) -> bool { |
