Rollup merge of #126841 - c410-f3r:concat-again, r=petrochenkov
[`macro_metavar_expr_concat`] Add support for literals
Adds support for things like `${concat($variable, 123)}` or `${concat("hello", "_world")}` .
cc #124225
This commit is contained in:
许杰友 Jieyou Xu (Joe)
GitHub
commit
2c16d65c1e
@ -1,4 +1,4 @@
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use rustc_ast::token::{self, Delimiter, IdentIsRaw};
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use rustc_ast::token::{self, Delimiter, IdentIsRaw, Lit, Token, TokenKind};
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use rustc_ast::tokenstream::{RefTokenTreeCursor, TokenStream, TokenTree};
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use rustc_ast::{LitIntType, LitKind};
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use rustc_ast_pretty::pprust;
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@ -6,9 +6,10 @@
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use rustc_macros::{Decodable, Encodable};
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use rustc_session::parse::ParseSess;
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use rustc_span::symbol::Ident;
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use rustc_span::Span;
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use rustc_span::{Span, Symbol};
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pub(crate) const RAW_IDENT_ERR: &str = "`${concat(..)}` currently does not support raw identifiers";
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pub(crate) const UNSUPPORTED_CONCAT_ELEM_ERR: &str = "expected identifier or string literal";
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/// A meta-variable expression, for expansions based on properties of meta-variables.
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#[derive(Debug, PartialEq, Encodable, Decodable)]
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@ -51,11 +52,26 @@ pub(crate) fn parse<'psess>(
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let mut result = Vec::new();
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loop {
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let is_var = try_eat_dollar(&mut iter);
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let element_ident = parse_ident(&mut iter, psess, outer_span)?;
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let token = parse_token(&mut iter, psess, outer_span)?;
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let element = if is_var {
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MetaVarExprConcatElem::Var(element_ident)
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MetaVarExprConcatElem::Var(parse_ident_from_token(psess, token)?)
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} else if let TokenKind::Literal(Lit {
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kind: token::LitKind::Str,
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symbol,
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suffix: None,
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}) = token.kind
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{
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MetaVarExprConcatElem::Literal(symbol)
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} else {
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MetaVarExprConcatElem::Ident(element_ident)
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match parse_ident_from_token(psess, token) {
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Err(err) => {
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err.cancel();
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return Err(psess
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.dcx()
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.struct_span_err(token.span, UNSUPPORTED_CONCAT_ELEM_ERR));
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}
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Ok(elem) => MetaVarExprConcatElem::Ident(elem),
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}
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};
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result.push(element);
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if iter.look_ahead(0).is_none() {
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@ -105,11 +121,13 @@ pub(crate) fn ident(&self) -> Option<Ident> {
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#[derive(Debug, Decodable, Encodable, PartialEq)]
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pub(crate) enum MetaVarExprConcatElem {
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/// There is NO preceding dollar sign, which means that this identifier should be interpreted
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/// as a literal.
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/// Identifier WITHOUT a preceding dollar sign, which means that this identifier should be
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/// interpreted as a literal.
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Ident(Ident),
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/// There is a preceding dollar sign, which means that this identifier should be expanded
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/// and interpreted as a variable.
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/// For example, a number or a string.
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Literal(Symbol),
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/// Identifier WITH a preceding dollar sign, which means that this identifier should be
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/// expanded and interpreted as a variable.
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Var(Ident),
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}
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@ -158,7 +176,7 @@ fn parse_depth<'psess>(
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span: Span,
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) -> PResult<'psess, usize> {
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let Some(tt) = iter.next() else { return Ok(0) };
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let TokenTree::Token(token::Token { kind: token::TokenKind::Literal(lit), .. }, _) = tt else {
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let TokenTree::Token(Token { kind: TokenKind::Literal(lit), .. }, _) = tt else {
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return Err(psess
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.dcx()
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.struct_span_err(span, "meta-variable expression depth must be a literal"));
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@ -180,12 +198,14 @@ fn parse_ident<'psess>(
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psess: &'psess ParseSess,
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fallback_span: Span,
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) -> PResult<'psess, Ident> {
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let Some(tt) = iter.next() else {
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return Err(psess.dcx().struct_span_err(fallback_span, "expected identifier"));
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};
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let TokenTree::Token(token, _) = tt else {
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return Err(psess.dcx().struct_span_err(tt.span(), "expected identifier"));
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};
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let token = parse_token(iter, psess, fallback_span)?;
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parse_ident_from_token(psess, token)
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}
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fn parse_ident_from_token<'psess>(
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psess: &'psess ParseSess,
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token: &Token,
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) -> PResult<'psess, Ident> {
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if let Some((elem, is_raw)) = token.ident() {
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if let IdentIsRaw::Yes = is_raw {
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return Err(psess.dcx().struct_span_err(elem.span, RAW_IDENT_ERR));
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@ -205,10 +225,24 @@ fn parse_ident<'psess>(
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Err(err)
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}
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fn parse_token<'psess, 't>(
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iter: &mut RefTokenTreeCursor<'t>,
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psess: &'psess ParseSess,
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fallback_span: Span,
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) -> PResult<'psess, &'t Token> {
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let Some(tt) = iter.next() else {
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return Err(psess.dcx().struct_span_err(fallback_span, UNSUPPORTED_CONCAT_ELEM_ERR));
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};
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let TokenTree::Token(token, _) = tt else {
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return Err(psess.dcx().struct_span_err(tt.span(), UNSUPPORTED_CONCAT_ELEM_ERR));
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};
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Ok(token)
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}
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/// Tries to move the iterator forward returning `true` if there is a comma. If not, then the
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/// iterator is not modified and the result is `false`.
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fn try_eat_comma(iter: &mut RefTokenTreeCursor<'_>) -> bool {
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if let Some(TokenTree::Token(token::Token { kind: token::Comma, .. }, _)) = iter.look_ahead(0) {
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if let Some(TokenTree::Token(Token { kind: token::Comma, .. }, _)) = iter.look_ahead(0) {
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let _ = iter.next();
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return true;
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}
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@ -218,8 +252,7 @@ fn try_eat_comma(iter: &mut RefTokenTreeCursor<'_>) -> bool {
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/// Tries to move the iterator forward returning `true` if there is a dollar sign. If not, then the
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/// iterator is not modified and the result is `false`.
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fn try_eat_dollar(iter: &mut RefTokenTreeCursor<'_>) -> bool {
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if let Some(TokenTree::Token(token::Token { kind: token::Dollar, .. }, _)) = iter.look_ahead(0)
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{
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if let Some(TokenTree::Token(Token { kind: token::Dollar, .. }, _)) = iter.look_ahead(0) {
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let _ = iter.next();
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return true;
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}
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@ -232,8 +265,7 @@ fn eat_dollar<'psess>(
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psess: &'psess ParseSess,
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span: Span,
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) -> PResult<'psess, ()> {
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if let Some(TokenTree::Token(token::Token { kind: token::Dollar, .. }, _)) = iter.look_ahead(0)
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{
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if let Some(TokenTree::Token(Token { kind: token::Dollar, .. }, _)) = iter.look_ahead(0) {
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let _ = iter.next();
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return Ok(());
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}
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@ -11,11 +11,13 @@
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use rustc_ast::tokenstream::{DelimSpacing, DelimSpan, Spacing, TokenStream, TokenTree};
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use rustc_data_structures::fx::FxHashMap;
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use rustc_errors::{pluralize, Diag, DiagCtxtHandle, PResult};
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use rustc_parse::lexer::nfc_normalize;
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use rustc_parse::parser::ParseNtResult;
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use rustc_session::parse::ParseSess;
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use rustc_session::parse::SymbolGallery;
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use rustc_span::hygiene::{LocalExpnId, Transparency};
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use rustc_span::symbol::{sym, Ident, MacroRulesNormalizedIdent};
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use rustc_span::{with_metavar_spans, Span, Symbol, SyntaxContext};
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use rustc_span::{with_metavar_spans, Span, SyntaxContext};
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use smallvec::{smallvec, SmallVec};
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use std::mem;
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@ -312,7 +314,16 @@ pub(super) fn transcribe<'a>(
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// Replace meta-variable expressions with the result of their expansion.
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mbe::TokenTree::MetaVarExpr(sp, expr) => {
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transcribe_metavar_expr(dcx, expr, interp, &mut marker, &repeats, &mut result, sp)?;
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transcribe_metavar_expr(
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dcx,
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expr,
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interp,
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&mut marker,
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&repeats,
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&mut result,
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sp,
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&psess.symbol_gallery,
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)?;
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}
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// If we are entering a new delimiter, we push its contents to the `stack` to be
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@ -669,6 +680,7 @@ fn transcribe_metavar_expr<'a>(
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repeats: &[(usize, usize)],
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result: &mut Vec<TokenTree>,
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sp: &DelimSpan,
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symbol_gallery: &SymbolGallery,
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) -> PResult<'a, ()> {
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let mut visited_span = || {
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let mut span = sp.entire();
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@ -680,16 +692,26 @@ fn transcribe_metavar_expr<'a>(
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let mut concatenated = String::new();
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for element in elements.into_iter() {
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let string = match element {
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MetaVarExprConcatElem::Ident(ident) => ident.to_string(),
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MetaVarExprConcatElem::Var(ident) => extract_ident(dcx, *ident, interp)?,
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MetaVarExprConcatElem::Ident(elem) => elem.to_string(),
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MetaVarExprConcatElem::Literal(elem) => elem.as_str().into(),
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MetaVarExprConcatElem::Var(elem) => extract_ident(dcx, *elem, interp)?,
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};
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concatenated.push_str(&string);
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}
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let symbol = nfc_normalize(&concatenated);
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let concatenated_span = visited_span();
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if !rustc_lexer::is_ident(symbol.as_str()) {
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return Err(dcx.struct_span_err(
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concatenated_span,
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"`${concat(..)}` is not generating a valid identifier",
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));
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}
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symbol_gallery.insert(symbol, concatenated_span);
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// The current implementation marks the span as coming from the macro regardless of
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// contexts of the concatenated identifiers but this behavior may change in the
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// future.
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result.push(TokenTree::Token(
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Token::from_ast_ident(Ident::new(Symbol::intern(&concatenated), visited_span())),
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Token::from_ast_ident(Ident::new(symbol, concatenated_span)),
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Spacing::Alone,
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));
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}
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@ -37,6 +37,16 @@ macro_rules! without_dollar_sign_is_an_ident {
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};
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}
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macro_rules! literals {
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($ident:ident) => {{
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let ${concat(_a, "_b")}: () = ();
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let ${concat("_b", _a)}: () = ();
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let ${concat($ident, "_b")}: () = ();
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let ${concat("_b", $ident)}: () = ();
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}};
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}
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fn main() {
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create_things!(behold);
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behold_separated_idents_in_a_fn();
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@ -55,4 +65,6 @@ fn main() {
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without_dollar_sign_is_an_ident!(_123);
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assert_eq!(VARident, 1);
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assert_eq!(VAR_123, 2);
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literals!(_hello);
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}
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@ -26,14 +26,14 @@ macro_rules! idents_11 {
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macro_rules! no_params {
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() => {
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let ${concat(r#abc, abc)}: () = ();
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//~^ ERROR `${concat(..)}` currently does not support raw identifiers
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//~^ ERROR expected identifier or string literal
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//~| ERROR expected pattern, found `$`
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let ${concat(abc, r#abc)}: () = ();
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//~^ ERROR `${concat(..)}` currently does not support raw identifiers
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//~^ ERROR expected identifier or string literal
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let ${concat(r#abc, r#abc)}: () = ();
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//~^ ERROR `${concat(..)}` currently does not support raw identifiers
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//~^ ERROR expected identifier or string literal
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};
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}
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@ -1,16 +1,16 @@
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error: `${concat(..)}` currently does not support raw identifiers
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error: expected identifier or string literal
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--> $DIR/raw-identifiers.rs:28:22
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LL | let ${concat(r#abc, abc)}: () = ();
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| ^^^^^
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error: `${concat(..)}` currently does not support raw identifiers
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error: expected identifier or string literal
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--> $DIR/raw-identifiers.rs:32:27
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|
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LL | let ${concat(abc, r#abc)}: () = ();
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| ^^^^^
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error: `${concat(..)}` currently does not support raw identifiers
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error: expected identifier or string literal
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--> $DIR/raw-identifiers.rs:35:22
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|
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LL | let ${concat(r#abc, r#abc)}: () = ();
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@ -11,9 +11,6 @@ macro_rules! wrong_concat_declarations {
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${concat(aaaa,)}
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//~^ ERROR expected identifier
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${concat(aaaa, 1)}
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//~^ ERROR expected identifier
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${concat(_, aaaa)}
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${concat(aaaa aaaa)}
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@ -30,9 +27,6 @@ macro_rules! wrong_concat_declarations {
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${concat($ex, aaaa,)}
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//~^ ERROR expected identifier
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${concat($ex, aaaa, 123)}
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//~^ ERROR expected identifier
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};
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}
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@ -43,8 +37,80 @@ macro_rules! dollar_sign_without_referenced_ident {
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};
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}
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macro_rules! starting_number {
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($ident:ident) => {{
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let ${concat("1", $ident)}: () = ();
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//~^ ERROR `${concat(..)}` is not generating a valid identifier
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}};
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}
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macro_rules! starting_valid_unicode {
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($ident:ident) => {{
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let ${concat("Ý", $ident)}: () = ();
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}};
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}
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macro_rules! starting_invalid_unicode {
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($ident:ident) => {{
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let ${concat("\u{00BD}", $ident)}: () = ();
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//~^ ERROR `${concat(..)}` is not generating a valid identifier
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}};
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}
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macro_rules! ending_number {
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($ident:ident) => {{
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let ${concat($ident, "1")}: () = ();
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}};
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}
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macro_rules! ending_valid_unicode {
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($ident:ident) => {{
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let ${concat($ident, "Ý")}: () = ();
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}};
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}
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macro_rules! ending_invalid_unicode {
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($ident:ident) => {{
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let ${concat($ident, "\u{00BD}")}: () = ();
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//~^ ERROR `${concat(..)}` is not generating a valid identifier
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}};
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}
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macro_rules! empty {
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() => {{
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let ${concat("", "")}: () = ();
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//~^ ERROR `${concat(..)}` is not generating a valid identifier
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}};
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}
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macro_rules! unsupported_literals {
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($ident:ident) => {{
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let ${concat(_a, 'b')}: () = ();
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//~^ ERROR expected identifier or string literal
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//~| ERROR expected pattern
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let ${concat(_a, 1)}: () = ();
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//~^ ERROR expected identifier or string literal
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let ${concat($ident, 'b')}: () = ();
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//~^ ERROR expected identifier or string literal
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let ${concat($ident, 1)}: () = ();
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//~^ ERROR expected identifier or string literal
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}};
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}
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fn main() {
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wrong_concat_declarations!(1);
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dollar_sign_without_referenced_ident!(VAR);
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starting_number!(_abc);
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starting_valid_unicode!(_abc);
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starting_invalid_unicode!(_abc);
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ending_number!(_abc);
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ending_valid_unicode!(_abc);
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ending_invalid_unicode!(_abc);
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unsupported_literals!(_abc);
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empty!();
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}
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@ -1,4 +1,4 @@
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error: expected identifier
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error: expected identifier or string literal
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--> $DIR/syntax-errors.rs:5:10
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|
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LL | ${concat()}
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@ -10,59 +10,126 @@ error: `concat` must have at least two elements
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LL | ${concat(aaaa)}
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| ^^^^^^
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error: expected identifier
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error: expected identifier or string literal
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--> $DIR/syntax-errors.rs:11:10
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|
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LL | ${concat(aaaa,)}
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| ^^^^^^^^^^^^^^^
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error: expected identifier, found `1`
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--> $DIR/syntax-errors.rs:14:24
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|
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LL | ${concat(aaaa, 1)}
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| ^ help: try removing `1`
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error: expected comma
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--> $DIR/syntax-errors.rs:19:10
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--> $DIR/syntax-errors.rs:16:10
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|
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LL | ${concat(aaaa aaaa)}
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| ^^^^^^^^^^^^^^^^^^^
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error: `concat` must have at least two elements
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--> $DIR/syntax-errors.rs:22:11
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--> $DIR/syntax-errors.rs:19:11
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|
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LL | ${concat($ex)}
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| ^^^^^^
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error: expected comma
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--> $DIR/syntax-errors.rs:28:10
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--> $DIR/syntax-errors.rs:25:10
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|
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LL | ${concat($ex, aaaa 123)}
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| ^^^^^^^^^^^^^^^^^^^^^^^
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error: expected identifier
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--> $DIR/syntax-errors.rs:31:10
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error: expected identifier or string literal
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--> $DIR/syntax-errors.rs:28:10
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|
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LL | ${concat($ex, aaaa,)}
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| ^^^^^^^^^^^^^^^^^^^^
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error: expected identifier, found `123`
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--> $DIR/syntax-errors.rs:34:29
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error: expected identifier or string literal
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--> $DIR/syntax-errors.rs:88:26
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|
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LL | ${concat($ex, aaaa, 123)}
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| ^^^ help: try removing `123`
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LL | let ${concat(_a, 'b')}: () = ();
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| ^^^
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error: expected identifier or string literal
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--> $DIR/syntax-errors.rs:91:26
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|
|
||||
LL | let ${concat(_a, 1)}: () = ();
|
||||
| ^
|
||||
|
||||
error: expected identifier or string literal
|
||||
--> $DIR/syntax-errors.rs:94:30
|
||||
|
|
||||
LL | let ${concat($ident, 'b')}: () = ();
|
||||
| ^^^
|
||||
|
||||
error: expected identifier or string literal
|
||||
--> $DIR/syntax-errors.rs:96:30
|
||||
|
|
||||
LL | let ${concat($ident, 1)}: () = ();
|
||||
| ^
|
||||
|
||||
error: `${concat(..)}` currently only accepts identifiers or meta-variables as parameters
|
||||
--> $DIR/syntax-errors.rs:25:19
|
||||
--> $DIR/syntax-errors.rs:22:19
|
||||
|
|
||||
LL | ${concat($ex, aaaa)}
|
||||
| ^^
|
||||
|
||||
error: variable `foo` is not recognized in meta-variable expression
|
||||
--> $DIR/syntax-errors.rs:41:30
|
||||
--> $DIR/syntax-errors.rs:35:30
|
||||
|
|
||||
LL | const ${concat(FOO, $foo)}: i32 = 2;
|
||||
| ^^^
|
||||
|
||||
error: aborting due to 11 previous errors
|
||||
error: `${concat(..)}` is not generating a valid identifier
|
||||
--> $DIR/syntax-errors.rs:42:14
|
||||
|
|
||||
LL | let ${concat("1", $ident)}: () = ();
|
||||
| ^^^^^^^^^^^^^^^^^^^^^
|
||||
...
|
||||
LL | starting_number!(_abc);
|
||||
| ---------------------- in this macro invocation
|
||||
|
|
||||
= note: this error originates in the macro `starting_number` (in Nightly builds, run with -Z macro-backtrace for more info)
|
||||
|
||||
error: `${concat(..)}` is not generating a valid identifier
|
||||
--> $DIR/syntax-errors.rs:55:14
|
||||
|
|
||||
LL | let ${concat("\u{00BD}", $ident)}: () = ();
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
...
|
||||
LL | starting_invalid_unicode!(_abc);
|
||||
| ------------------------------- in this macro invocation
|
||||
|
|
||||
= note: this error originates in the macro `starting_invalid_unicode` (in Nightly builds, run with -Z macro-backtrace for more info)
|
||||
|
||||
error: `${concat(..)}` is not generating a valid identifier
|
||||
--> $DIR/syntax-errors.rs:74:14
|
||||
|
|
||||
LL | let ${concat($ident, "\u{00BD}")}: () = ();
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
...
|
||||
LL | ending_invalid_unicode!(_abc);
|
||||
| ----------------------------- in this macro invocation
|
||||
|
|
||||
= note: this error originates in the macro `ending_invalid_unicode` (in Nightly builds, run with -Z macro-backtrace for more info)
|
||||
|
||||
error: expected pattern, found `$`
|
||||
--> $DIR/syntax-errors.rs:88:13
|
||||
|
|
||||
LL | let ${concat(_a, 'b')}: () = ();
|
||||
| ^ expected pattern
|
||||
...
|
||||
LL | unsupported_literals!(_abc);
|
||||
| --------------------------- in this macro invocation
|
||||
|
|
||||
= note: this error originates in the macro `unsupported_literals` (in Nightly builds, run with -Z macro-backtrace for more info)
|
||||
|
||||
error: `${concat(..)}` is not generating a valid identifier
|
||||
--> $DIR/syntax-errors.rs:81:14
|
||||
|
|
||||
LL | let ${concat("", "")}: () = ();
|
||||
| ^^^^^^^^^^^^^^^^
|
||||
...
|
||||
LL | empty!();
|
||||
| -------- in this macro invocation
|
||||
|
|
||||
= note: this error originates in the macro `empty` (in Nightly builds, run with -Z macro-backtrace for more info)
|
||||
|
||||
error: aborting due to 18 previous errors
|
||||
|
||||
|
||||
@ -0,0 +1,14 @@
|
||||
//@ run-pass
|
||||
|
||||
#![feature(macro_metavar_expr_concat)]
|
||||
|
||||
macro_rules! turn_to_page {
|
||||
($ident:ident) => {
|
||||
const ${concat("Ḧ", $ident)}: i32 = 394;
|
||||
};
|
||||
}
|
||||
|
||||
fn main() {
|
||||
turn_to_page!(P);
|
||||
assert_eq!(ḦP, 394);
|
||||
}
|
||||
@ -190,7 +190,7 @@ error: unrecognized meta-variable expression
|
||||
LL | ( $( $i:ident ),* ) => { ${ aaaaaaaaaaaaaa(i) } };
|
||||
| ^^^^^^^^^^^^^^ help: supported expressions are count, ignore, index and len
|
||||
|
||||
error: expected identifier
|
||||
error: expected identifier or string literal
|
||||
--> $DIR/syntax-errors.rs:118:33
|
||||
|
|
||||
LL | ( $( $i:ident ),* ) => { ${ {} } };
|
||||
|
||||
Loading…
Reference in New Issue
Block a user