| // Copyright 2015 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| use ast::{self, Arg, Arm, Block, Expr, Item, Pat, Stmt, Ty}; |
| use syntax_pos::Span; |
| use ext::base::ExtCtxt; |
| use ext::base; |
| use ext::build::AstBuilder; |
| use parse::parser::{Parser, PathStyle}; |
| use parse::token::*; |
| use parse::token; |
| use ptr::P; |
| use tokenstream::{self, TokenTree}; |
| |
| /// Quasiquoting works via token trees. |
| /// |
| /// This is registered as a set of expression syntax extension called quote! |
| /// that lifts its argument token-tree to an AST representing the |
| /// construction of the same token tree, with token::SubstNt interpreted |
| /// as antiquotes (splices). |
| |
| pub mod rt { |
| use ast; |
| use codemap::Spanned; |
| use ext::base::ExtCtxt; |
| use parse::{self, token, classify}; |
| use ptr::P; |
| use std::rc::Rc; |
| |
| use tokenstream::{self, TokenTree}; |
| |
| pub use parse::new_parser_from_tts; |
| pub use syntax_pos::{BytePos, Span, DUMMY_SP}; |
| pub use codemap::{dummy_spanned}; |
| |
| pub trait ToTokens { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree>; |
| } |
| |
| impl ToTokens for TokenTree { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec!(self.clone()) |
| } |
| } |
| |
| impl<T: ToTokens> ToTokens for Vec<T> { |
| fn to_tokens(&self, cx: &ExtCtxt) -> Vec<TokenTree> { |
| self.iter().flat_map(|t| t.to_tokens(cx)).collect() |
| } |
| } |
| |
| impl<T: ToTokens> ToTokens for Spanned<T> { |
| fn to_tokens(&self, cx: &ExtCtxt) -> Vec<TokenTree> { |
| // FIXME: use the span? |
| self.node.to_tokens(cx) |
| } |
| } |
| |
| impl<T: ToTokens> ToTokens for Option<T> { |
| fn to_tokens(&self, cx: &ExtCtxt) -> Vec<TokenTree> { |
| match *self { |
| Some(ref t) => t.to_tokens(cx), |
| None => Vec::new(), |
| } |
| } |
| } |
| |
| impl ToTokens for ast::Ident { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(DUMMY_SP, token::Ident(*self))] |
| } |
| } |
| |
| impl ToTokens for ast::Path { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(DUMMY_SP, |
| token::Interpolated(token::NtPath(Box::new(self.clone()))))] |
| } |
| } |
| |
| impl ToTokens for ast::Ty { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(self.span, token::Interpolated(token::NtTy(P(self.clone()))))] |
| } |
| } |
| |
| impl ToTokens for ast::Block { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(self.span, token::Interpolated(token::NtBlock(P(self.clone()))))] |
| } |
| } |
| |
| impl ToTokens for ast::Generics { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(DUMMY_SP, token::Interpolated(token::NtGenerics(self.clone())))] |
| } |
| } |
| |
| impl ToTokens for ast::WhereClause { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(DUMMY_SP, |
| token::Interpolated(token::NtWhereClause(self.clone())))] |
| } |
| } |
| |
| impl ToTokens for P<ast::Item> { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(self.span, token::Interpolated(token::NtItem(self.clone())))] |
| } |
| } |
| |
| impl ToTokens for ast::ImplItem { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(self.span, |
| token::Interpolated(token::NtImplItem(P(self.clone()))))] |
| } |
| } |
| |
| impl ToTokens for P<ast::ImplItem> { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(self.span, token::Interpolated(token::NtImplItem(self.clone())))] |
| } |
| } |
| |
| impl ToTokens for ast::TraitItem { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(self.span, |
| token::Interpolated(token::NtTraitItem(P(self.clone()))))] |
| } |
| } |
| |
| impl ToTokens for ast::Stmt { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| let mut tts = vec![ |
| TokenTree::Token(self.span, token::Interpolated(token::NtStmt(P(self.clone())))) |
| ]; |
| |
| // Some statements require a trailing semicolon. |
| if classify::stmt_ends_with_semi(&self.node) { |
| tts.push(TokenTree::Token(self.span, token::Semi)); |
| } |
| |
| tts |
| } |
| } |
| |
| impl ToTokens for P<ast::Expr> { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(self.span, token::Interpolated(token::NtExpr(self.clone())))] |
| } |
| } |
| |
| impl ToTokens for P<ast::Pat> { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(self.span, token::Interpolated(token::NtPat(self.clone())))] |
| } |
| } |
| |
| impl ToTokens for ast::Arm { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(DUMMY_SP, token::Interpolated(token::NtArm(self.clone())))] |
| } |
| } |
| |
| impl ToTokens for ast::Arg { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(DUMMY_SP, token::Interpolated(token::NtArg(self.clone())))] |
| } |
| } |
| |
| impl ToTokens for P<ast::Block> { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(DUMMY_SP, token::Interpolated(token::NtBlock(self.clone())))] |
| } |
| } |
| |
| macro_rules! impl_to_tokens_slice { |
| ($t: ty, $sep: expr) => { |
| impl ToTokens for [$t] { |
| fn to_tokens(&self, cx: &ExtCtxt) -> Vec<TokenTree> { |
| let mut v = vec![]; |
| for (i, x) in self.iter().enumerate() { |
| if i > 0 { |
| v.extend_from_slice(&$sep); |
| } |
| v.extend(x.to_tokens(cx)); |
| } |
| v |
| } |
| } |
| }; |
| } |
| |
| impl_to_tokens_slice! { ast::Ty, [TokenTree::Token(DUMMY_SP, token::Comma)] } |
| impl_to_tokens_slice! { P<ast::Item>, [] } |
| impl_to_tokens_slice! { ast::Arg, [TokenTree::Token(DUMMY_SP, token::Comma)] } |
| |
| impl ToTokens for P<ast::MetaItem> { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Token(DUMMY_SP, token::Interpolated(token::NtMeta(self.clone())))] |
| } |
| } |
| |
| impl ToTokens for ast::Attribute { |
| fn to_tokens(&self, cx: &ExtCtxt) -> Vec<TokenTree> { |
| let mut r = vec![]; |
| // FIXME: The spans could be better |
| r.push(TokenTree::Token(self.span, token::Pound)); |
| if self.node.style == ast::AttrStyle::Inner { |
| r.push(TokenTree::Token(self.span, token::Not)); |
| } |
| r.push(TokenTree::Delimited(self.span, Rc::new(tokenstream::Delimited { |
| delim: token::Bracket, |
| open_span: self.span, |
| tts: self.node.value.to_tokens(cx), |
| close_span: self.span, |
| }))); |
| r |
| } |
| } |
| |
| impl ToTokens for str { |
| fn to_tokens(&self, cx: &ExtCtxt) -> Vec<TokenTree> { |
| let lit = ast::LitKind::Str( |
| token::intern_and_get_ident(self), ast::StrStyle::Cooked); |
| dummy_spanned(lit).to_tokens(cx) |
| } |
| } |
| |
| impl ToTokens for () { |
| fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> { |
| vec![TokenTree::Delimited(DUMMY_SP, Rc::new(tokenstream::Delimited { |
| delim: token::Paren, |
| open_span: DUMMY_SP, |
| tts: vec![], |
| close_span: DUMMY_SP, |
| }))] |
| } |
| } |
| |
| impl ToTokens for ast::Lit { |
| fn to_tokens(&self, cx: &ExtCtxt) -> Vec<TokenTree> { |
| // FIXME: This is wrong |
| P(ast::Expr { |
| id: ast::DUMMY_NODE_ID, |
| node: ast::ExprKind::Lit(P(self.clone())), |
| span: DUMMY_SP, |
| attrs: ast::ThinVec::new(), |
| }).to_tokens(cx) |
| } |
| } |
| |
| impl ToTokens for bool { |
| fn to_tokens(&self, cx: &ExtCtxt) -> Vec<TokenTree> { |
| dummy_spanned(ast::LitKind::Bool(*self)).to_tokens(cx) |
| } |
| } |
| |
| impl ToTokens for char { |
| fn to_tokens(&self, cx: &ExtCtxt) -> Vec<TokenTree> { |
| dummy_spanned(ast::LitKind::Char(*self)).to_tokens(cx) |
| } |
| } |
| |
| macro_rules! impl_to_tokens_int { |
| (signed, $t:ty, $tag:expr) => ( |
| impl ToTokens for $t { |
| fn to_tokens(&self, cx: &ExtCtxt) -> Vec<TokenTree> { |
| let val = if *self < 0 { |
| -self |
| } else { |
| *self |
| }; |
| let lit = ast::LitKind::Int(val as u64, ast::LitIntType::Signed($tag)); |
| let lit = P(ast::Expr { |
| id: ast::DUMMY_NODE_ID, |
| node: ast::ExprKind::Lit(P(dummy_spanned(lit))), |
| span: DUMMY_SP, |
| attrs: ast::ThinVec::new(), |
| }); |
| if *self >= 0 { |
| return lit.to_tokens(cx); |
| } |
| P(ast::Expr { |
| id: ast::DUMMY_NODE_ID, |
| node: ast::ExprKind::Unary(ast::UnOp::Neg, lit), |
| span: DUMMY_SP, |
| attrs: ast::ThinVec::new(), |
| }).to_tokens(cx) |
| } |
| } |
| ); |
| (unsigned, $t:ty, $tag:expr) => ( |
| impl ToTokens for $t { |
| fn to_tokens(&self, cx: &ExtCtxt) -> Vec<TokenTree> { |
| let lit = ast::LitKind::Int(*self as u64, ast::LitIntType::Unsigned($tag)); |
| dummy_spanned(lit).to_tokens(cx) |
| } |
| } |
| ); |
| } |
| |
| impl_to_tokens_int! { signed, isize, ast::IntTy::Is } |
| impl_to_tokens_int! { signed, i8, ast::IntTy::I8 } |
| impl_to_tokens_int! { signed, i16, ast::IntTy::I16 } |
| impl_to_tokens_int! { signed, i32, ast::IntTy::I32 } |
| impl_to_tokens_int! { signed, i64, ast::IntTy::I64 } |
| |
| impl_to_tokens_int! { unsigned, usize, ast::UintTy::Us } |
| impl_to_tokens_int! { unsigned, u8, ast::UintTy::U8 } |
| impl_to_tokens_int! { unsigned, u16, ast::UintTy::U16 } |
| impl_to_tokens_int! { unsigned, u32, ast::UintTy::U32 } |
| impl_to_tokens_int! { unsigned, u64, ast::UintTy::U64 } |
| |
| pub trait ExtParseUtils { |
| fn parse_item(&self, s: String) -> P<ast::Item>; |
| fn parse_expr(&self, s: String) -> P<ast::Expr>; |
| fn parse_stmt(&self, s: String) -> ast::Stmt; |
| fn parse_tts(&self, s: String) -> Vec<TokenTree>; |
| } |
| |
| impl<'a> ExtParseUtils for ExtCtxt<'a> { |
| fn parse_item(&self, s: String) -> P<ast::Item> { |
| panictry!(parse::parse_item_from_source_str( |
| "<quote expansion>".to_string(), |
| s, |
| self.cfg(), |
| self.parse_sess())).expect("parse error") |
| } |
| |
| fn parse_stmt(&self, s: String) -> ast::Stmt { |
| panictry!(parse::parse_stmt_from_source_str( |
| "<quote expansion>".to_string(), |
| s, |
| self.cfg(), |
| self.parse_sess())).expect("parse error") |
| } |
| |
| fn parse_expr(&self, s: String) -> P<ast::Expr> { |
| panictry!(parse::parse_expr_from_source_str( |
| "<quote expansion>".to_string(), |
| s, |
| self.cfg(), |
| self.parse_sess())) |
| } |
| |
| fn parse_tts(&self, s: String) -> Vec<TokenTree> { |
| panictry!(parse::parse_tts_from_source_str( |
| "<quote expansion>".to_string(), |
| s, |
| self.cfg(), |
| self.parse_sess())) |
| } |
| } |
| } |
| |
| // These panicking parsing functions are used by the quote_*!() syntax extensions, |
| // but shouldn't be used otherwise. |
| pub fn parse_expr_panic(parser: &mut Parser) -> P<Expr> { |
| panictry!(parser.parse_expr()) |
| } |
| |
| pub fn parse_item_panic(parser: &mut Parser) -> Option<P<Item>> { |
| panictry!(parser.parse_item()) |
| } |
| |
| pub fn parse_pat_panic(parser: &mut Parser) -> P<Pat> { |
| panictry!(parser.parse_pat()) |
| } |
| |
| pub fn parse_arm_panic(parser: &mut Parser) -> Arm { |
| panictry!(parser.parse_arm()) |
| } |
| |
| pub fn parse_ty_panic(parser: &mut Parser) -> P<Ty> { |
| panictry!(parser.parse_ty()) |
| } |
| |
| pub fn parse_stmt_panic(parser: &mut Parser) -> Option<Stmt> { |
| panictry!(parser.parse_stmt()) |
| } |
| |
| pub fn parse_attribute_panic(parser: &mut Parser, permit_inner: bool) -> ast::Attribute { |
| panictry!(parser.parse_attribute(permit_inner)) |
| } |
| |
| pub fn parse_arg_panic(parser: &mut Parser) -> Arg { |
| panictry!(parser.parse_arg()) |
| } |
| |
| pub fn parse_block_panic(parser: &mut Parser) -> P<Block> { |
| panictry!(parser.parse_block()) |
| } |
| |
| pub fn parse_meta_item_panic(parser: &mut Parser) -> P<ast::MetaItem> { |
| panictry!(parser.parse_meta_item()) |
| } |
| |
| pub fn parse_path_panic(parser: &mut Parser, mode: PathStyle) -> ast::Path { |
| panictry!(parser.parse_path(mode)) |
| } |
| |
| pub fn expand_quote_tokens<'cx>(cx: &'cx mut ExtCtxt, |
| sp: Span, |
| tts: &[TokenTree]) |
| -> Box<base::MacResult+'cx> { |
| let (cx_expr, expr) = expand_tts(cx, sp, tts); |
| let expanded = expand_wrapper(cx, sp, cx_expr, expr, &[&["syntax", "ext", "quote", "rt"]]); |
| base::MacEager::expr(expanded) |
| } |
| |
| pub fn expand_quote_expr<'cx>(cx: &'cx mut ExtCtxt, |
| sp: Span, |
| tts: &[TokenTree]) |
| -> Box<base::MacResult+'cx> { |
| let expanded = expand_parse_call(cx, sp, "parse_expr_panic", vec!(), tts); |
| base::MacEager::expr(expanded) |
| } |
| |
| pub fn expand_quote_item<'cx>(cx: &'cx mut ExtCtxt, |
| sp: Span, |
| tts: &[TokenTree]) |
| -> Box<base::MacResult+'cx> { |
| let expanded = expand_parse_call(cx, sp, "parse_item_panic", vec!(), tts); |
| base::MacEager::expr(expanded) |
| } |
| |
| pub fn expand_quote_pat<'cx>(cx: &'cx mut ExtCtxt, |
| sp: Span, |
| tts: &[TokenTree]) |
| -> Box<base::MacResult+'cx> { |
| let expanded = expand_parse_call(cx, sp, "parse_pat_panic", vec!(), tts); |
| base::MacEager::expr(expanded) |
| } |
| |
| pub fn expand_quote_arm(cx: &mut ExtCtxt, |
| sp: Span, |
| tts: &[TokenTree]) |
| -> Box<base::MacResult+'static> { |
| let expanded = expand_parse_call(cx, sp, "parse_arm_panic", vec!(), tts); |
| base::MacEager::expr(expanded) |
| } |
| |
| pub fn expand_quote_ty(cx: &mut ExtCtxt, |
| sp: Span, |
| tts: &[TokenTree]) |
| -> Box<base::MacResult+'static> { |
| let expanded = expand_parse_call(cx, sp, "parse_ty_panic", vec!(), tts); |
| base::MacEager::expr(expanded) |
| } |
| |
| pub fn expand_quote_stmt(cx: &mut ExtCtxt, |
| sp: Span, |
| tts: &[TokenTree]) |
| -> Box<base::MacResult+'static> { |
| let expanded = expand_parse_call(cx, sp, "parse_stmt_panic", vec!(), tts); |
| base::MacEager::expr(expanded) |
| } |
| |
| pub fn expand_quote_attr(cx: &mut ExtCtxt, |
| sp: Span, |
| tts: &[TokenTree]) |
| -> Box<base::MacResult+'static> { |
| let expanded = expand_parse_call(cx, sp, "parse_attribute_panic", |
| vec!(cx.expr_bool(sp, true)), tts); |
| |
| base::MacEager::expr(expanded) |
| } |
| |
| pub fn expand_quote_arg(cx: &mut ExtCtxt, |
| sp: Span, |
| tts: &[TokenTree]) |
| -> Box<base::MacResult+'static> { |
| let expanded = expand_parse_call(cx, sp, "parse_arg_panic", vec!(), tts); |
| base::MacEager::expr(expanded) |
| } |
| |
| pub fn expand_quote_block(cx: &mut ExtCtxt, |
| sp: Span, |
| tts: &[TokenTree]) |
| -> Box<base::MacResult+'static> { |
| let expanded = expand_parse_call(cx, sp, "parse_block_panic", vec!(), tts); |
| base::MacEager::expr(expanded) |
| } |
| |
| pub fn expand_quote_meta_item(cx: &mut ExtCtxt, |
| sp: Span, |
| tts: &[TokenTree]) |
| -> Box<base::MacResult+'static> { |
| let expanded = expand_parse_call(cx, sp, "parse_meta_item_panic", vec!(), tts); |
| base::MacEager::expr(expanded) |
| } |
| |
| pub fn expand_quote_path(cx: &mut ExtCtxt, |
| sp: Span, |
| tts: &[TokenTree]) |
| -> Box<base::MacResult+'static> { |
| let mode = mk_parser_path(cx, sp, &["PathStyle", "Type"]); |
| let expanded = expand_parse_call(cx, sp, "parse_path_panic", vec!(mode), tts); |
| base::MacEager::expr(expanded) |
| } |
| |
| pub fn expand_quote_matcher(cx: &mut ExtCtxt, |
| sp: Span, |
| tts: &[TokenTree]) |
| -> Box<base::MacResult+'static> { |
| let (cx_expr, tts) = parse_arguments_to_quote(cx, tts); |
| let mut vector = mk_stmts_let(cx, sp); |
| vector.extend(statements_mk_tts(cx, &tts[..], true)); |
| vector.push(cx.stmt_expr(cx.expr_ident(sp, id_ext("tt")))); |
| let block = cx.expr_block(cx.block(sp, vector)); |
| |
| let expanded = expand_wrapper(cx, sp, cx_expr, block, &[&["syntax", "ext", "quote", "rt"]]); |
| base::MacEager::expr(expanded) |
| } |
| |
| fn ids_ext(strs: Vec<String> ) -> Vec<ast::Ident> { |
| strs.iter().map(|str| str_to_ident(&(*str))).collect() |
| } |
| |
| fn id_ext(str: &str) -> ast::Ident { |
| str_to_ident(str) |
| } |
| |
| // Lift an ident to the expr that evaluates to that ident. |
| fn mk_ident(cx: &ExtCtxt, sp: Span, ident: ast::Ident) -> P<ast::Expr> { |
| let e_str = cx.expr_str(sp, ident.name.as_str()); |
| cx.expr_method_call(sp, |
| cx.expr_ident(sp, id_ext("ext_cx")), |
| id_ext("ident_of"), |
| vec!(e_str)) |
| } |
| |
| // Lift a name to the expr that evaluates to that name |
| fn mk_name(cx: &ExtCtxt, sp: Span, ident: ast::Ident) -> P<ast::Expr> { |
| let e_str = cx.expr_str(sp, ident.name.as_str()); |
| cx.expr_method_call(sp, |
| cx.expr_ident(sp, id_ext("ext_cx")), |
| id_ext("name_of"), |
| vec!(e_str)) |
| } |
| |
| fn mk_tt_path(cx: &ExtCtxt, sp: Span, name: &str) -> P<ast::Expr> { |
| let idents = vec!(id_ext("syntax"), id_ext("tokenstream"), id_ext("TokenTree"), id_ext(name)); |
| cx.expr_path(cx.path_global(sp, idents)) |
| } |
| |
| fn mk_token_path(cx: &ExtCtxt, sp: Span, name: &str) -> P<ast::Expr> { |
| let idents = vec!(id_ext("syntax"), id_ext("parse"), id_ext("token"), id_ext(name)); |
| cx.expr_path(cx.path_global(sp, idents)) |
| } |
| |
| fn mk_parser_path(cx: &ExtCtxt, sp: Span, names: &[&str]) -> P<ast::Expr> { |
| let mut idents = vec![id_ext("syntax"), id_ext("parse"), id_ext("parser")]; |
| idents.extend(names.iter().cloned().map(id_ext)); |
| cx.expr_path(cx.path_global(sp, idents)) |
| } |
| |
| fn mk_binop(cx: &ExtCtxt, sp: Span, bop: token::BinOpToken) -> P<ast::Expr> { |
| let name = match bop { |
| token::Plus => "Plus", |
| token::Minus => "Minus", |
| token::Star => "Star", |
| token::Slash => "Slash", |
| token::Percent => "Percent", |
| token::Caret => "Caret", |
| token::And => "And", |
| token::Or => "Or", |
| token::Shl => "Shl", |
| token::Shr => "Shr" |
| }; |
| mk_token_path(cx, sp, name) |
| } |
| |
| fn mk_delim(cx: &ExtCtxt, sp: Span, delim: token::DelimToken) -> P<ast::Expr> { |
| let name = match delim { |
| token::Paren => "Paren", |
| token::Bracket => "Bracket", |
| token::Brace => "Brace", |
| token::NoDelim => "NoDelim", |
| }; |
| mk_token_path(cx, sp, name) |
| } |
| |
| #[allow(non_upper_case_globals)] |
| fn expr_mk_token(cx: &ExtCtxt, sp: Span, tok: &token::Token) -> P<ast::Expr> { |
| macro_rules! mk_lit { |
| ($name: expr, $suffix: expr, $($args: expr),*) => {{ |
| let inner = cx.expr_call(sp, mk_token_path(cx, sp, $name), vec![$($args),*]); |
| let suffix = match $suffix { |
| Some(name) => cx.expr_some(sp, mk_name(cx, sp, ast::Ident::with_empty_ctxt(name))), |
| None => cx.expr_none(sp) |
| }; |
| cx.expr_call(sp, mk_token_path(cx, sp, "Literal"), vec![inner, suffix]) |
| }} |
| } |
| match *tok { |
| token::BinOp(binop) => { |
| return cx.expr_call(sp, mk_token_path(cx, sp, "BinOp"), vec!(mk_binop(cx, sp, binop))); |
| } |
| token::BinOpEq(binop) => { |
| return cx.expr_call(sp, mk_token_path(cx, sp, "BinOpEq"), |
| vec!(mk_binop(cx, sp, binop))); |
| } |
| |
| token::OpenDelim(delim) => { |
| return cx.expr_call(sp, mk_token_path(cx, sp, "OpenDelim"), |
| vec![mk_delim(cx, sp, delim)]); |
| } |
| token::CloseDelim(delim) => { |
| return cx.expr_call(sp, mk_token_path(cx, sp, "CloseDelim"), |
| vec![mk_delim(cx, sp, delim)]); |
| } |
| |
| token::Literal(token::Byte(i), suf) => { |
| let e_byte = mk_name(cx, sp, ast::Ident::with_empty_ctxt(i)); |
| return mk_lit!("Byte", suf, e_byte); |
| } |
| |
| token::Literal(token::Char(i), suf) => { |
| let e_char = mk_name(cx, sp, ast::Ident::with_empty_ctxt(i)); |
| return mk_lit!("Char", suf, e_char); |
| } |
| |
| token::Literal(token::Integer(i), suf) => { |
| let e_int = mk_name(cx, sp, ast::Ident::with_empty_ctxt(i)); |
| return mk_lit!("Integer", suf, e_int); |
| } |
| |
| token::Literal(token::Float(fident), suf) => { |
| let e_fident = mk_name(cx, sp, ast::Ident::with_empty_ctxt(fident)); |
| return mk_lit!("Float", suf, e_fident); |
| } |
| |
| token::Literal(token::Str_(ident), suf) => { |
| return mk_lit!("Str_", suf, mk_name(cx, sp, ast::Ident::with_empty_ctxt(ident))) |
| } |
| |
| token::Literal(token::StrRaw(ident, n), suf) => { |
| return mk_lit!("StrRaw", suf, mk_name(cx, sp, ast::Ident::with_empty_ctxt(ident)), |
| cx.expr_usize(sp, n)) |
| } |
| |
| token::Ident(ident) => { |
| return cx.expr_call(sp, |
| mk_token_path(cx, sp, "Ident"), |
| vec![mk_ident(cx, sp, ident)]); |
| } |
| |
| token::Lifetime(ident) => { |
| return cx.expr_call(sp, |
| mk_token_path(cx, sp, "Lifetime"), |
| vec!(mk_ident(cx, sp, ident))); |
| } |
| |
| token::DocComment(ident) => { |
| return cx.expr_call(sp, |
| mk_token_path(cx, sp, "DocComment"), |
| vec!(mk_name(cx, sp, ast::Ident::with_empty_ctxt(ident)))); |
| } |
| |
| token::MatchNt(name, kind) => { |
| return cx.expr_call(sp, |
| mk_token_path(cx, sp, "MatchNt"), |
| vec![mk_ident(cx, sp, name), mk_ident(cx, sp, kind)]); |
| } |
| |
| token::Interpolated(_) => panic!("quote! with interpolated token"), |
| |
| _ => () |
| } |
| |
| let name = match *tok { |
| token::Eq => "Eq", |
| token::Lt => "Lt", |
| token::Le => "Le", |
| token::EqEq => "EqEq", |
| token::Ne => "Ne", |
| token::Ge => "Ge", |
| token::Gt => "Gt", |
| token::AndAnd => "AndAnd", |
| token::OrOr => "OrOr", |
| token::Not => "Not", |
| token::Tilde => "Tilde", |
| token::At => "At", |
| token::Dot => "Dot", |
| token::DotDot => "DotDot", |
| token::Comma => "Comma", |
| token::Semi => "Semi", |
| token::Colon => "Colon", |
| token::ModSep => "ModSep", |
| token::RArrow => "RArrow", |
| token::LArrow => "LArrow", |
| token::FatArrow => "FatArrow", |
| token::Pound => "Pound", |
| token::Dollar => "Dollar", |
| token::Question => "Question", |
| token::Underscore => "Underscore", |
| token::Eof => "Eof", |
| _ => panic!("unhandled token in quote!"), |
| }; |
| mk_token_path(cx, sp, name) |
| } |
| |
| fn statements_mk_tt(cx: &ExtCtxt, tt: &TokenTree, matcher: bool) -> Vec<ast::Stmt> { |
| match *tt { |
| TokenTree::Token(sp, SubstNt(ident)) => { |
| // tt.extend($ident.to_tokens(ext_cx)) |
| |
| let e_to_toks = |
| cx.expr_method_call(sp, |
| cx.expr_ident(sp, ident), |
| id_ext("to_tokens"), |
| vec!(cx.expr_ident(sp, id_ext("ext_cx")))); |
| let e_to_toks = |
| cx.expr_method_call(sp, e_to_toks, id_ext("into_iter"), vec![]); |
| |
| let e_push = |
| cx.expr_method_call(sp, |
| cx.expr_ident(sp, id_ext("tt")), |
| id_ext("extend"), |
| vec!(e_to_toks)); |
| |
| vec!(cx.stmt_expr(e_push)) |
| } |
| ref tt @ TokenTree::Token(_, MatchNt(..)) if !matcher => { |
| let mut seq = vec![]; |
| for i in 0..tt.len() { |
| seq.push(tt.get_tt(i)); |
| } |
| statements_mk_tts(cx, &seq[..], matcher) |
| } |
| TokenTree::Token(sp, ref tok) => { |
| let e_sp = cx.expr_ident(sp, id_ext("_sp")); |
| let e_tok = cx.expr_call(sp, |
| mk_tt_path(cx, sp, "Token"), |
| vec!(e_sp, expr_mk_token(cx, sp, tok))); |
| let e_push = |
| cx.expr_method_call(sp, |
| cx.expr_ident(sp, id_ext("tt")), |
| id_ext("push"), |
| vec!(e_tok)); |
| vec!(cx.stmt_expr(e_push)) |
| }, |
| TokenTree::Delimited(_, ref delimed) => { |
| statements_mk_tt(cx, &delimed.open_tt(), matcher).into_iter() |
| .chain(delimed.tts.iter() |
| .flat_map(|tt| statements_mk_tt(cx, tt, matcher))) |
| .chain(statements_mk_tt(cx, &delimed.close_tt(), matcher)) |
| .collect() |
| }, |
| TokenTree::Sequence(sp, ref seq) => { |
| if !matcher { |
| panic!("TokenTree::Sequence in quote!"); |
| } |
| |
| let e_sp = cx.expr_ident(sp, id_ext("_sp")); |
| |
| let stmt_let_tt = cx.stmt_let(sp, true, id_ext("tt"), cx.expr_vec_ng(sp)); |
| let mut tts_stmts = vec![stmt_let_tt]; |
| tts_stmts.extend(statements_mk_tts(cx, &seq.tts[..], matcher)); |
| tts_stmts.push(cx.stmt_expr(cx.expr_ident(sp, id_ext("tt")))); |
| let e_tts = cx.expr_block(cx.block(sp, tts_stmts)); |
| |
| let e_separator = match seq.separator { |
| Some(ref sep) => cx.expr_some(sp, expr_mk_token(cx, sp, sep)), |
| None => cx.expr_none(sp), |
| }; |
| let e_op = match seq.op { |
| tokenstream::KleeneOp::ZeroOrMore => "ZeroOrMore", |
| tokenstream::KleeneOp::OneOrMore => "OneOrMore", |
| }; |
| let e_op_idents = vec![ |
| id_ext("syntax"), |
| id_ext("tokenstream"), |
| id_ext("KleeneOp"), |
| id_ext(e_op), |
| ]; |
| let e_op = cx.expr_path(cx.path_global(sp, e_op_idents)); |
| let fields = vec![cx.field_imm(sp, id_ext("tts"), e_tts), |
| cx.field_imm(sp, id_ext("separator"), e_separator), |
| cx.field_imm(sp, id_ext("op"), e_op), |
| cx.field_imm(sp, id_ext("num_captures"), |
| cx.expr_usize(sp, seq.num_captures))]; |
| let seq_path = vec![id_ext("syntax"), |
| id_ext("tokenstream"), |
| id_ext("SequenceRepetition")]; |
| let e_seq_struct = cx.expr_struct(sp, cx.path_global(sp, seq_path), fields); |
| let e_rc_new = cx.expr_call_global(sp, vec![id_ext("std"), |
| id_ext("rc"), |
| id_ext("Rc"), |
| id_ext("new")], |
| vec![e_seq_struct]); |
| let e_tok = cx.expr_call(sp, |
| mk_tt_path(cx, sp, "Sequence"), |
| vec!(e_sp, e_rc_new)); |
| let e_push = |
| cx.expr_method_call(sp, |
| cx.expr_ident(sp, id_ext("tt")), |
| id_ext("push"), |
| vec!(e_tok)); |
| vec!(cx.stmt_expr(e_push)) |
| } |
| } |
| } |
| |
| fn parse_arguments_to_quote(cx: &ExtCtxt, tts: &[TokenTree]) |
| -> (P<ast::Expr>, Vec<TokenTree>) { |
| // NB: It appears that the main parser loses its mind if we consider |
| // $foo as a SubstNt during the main parse, so we have to re-parse |
| // under quote_depth > 0. This is silly and should go away; the _guess_ is |
| // it has to do with transition away from supporting old-style macros, so |
| // try removing it when enough of them are gone. |
| |
| let mut p = cx.new_parser_from_tts(tts); |
| p.quote_depth += 1; |
| |
| let cx_expr = panictry!(p.parse_expr()); |
| if !p.eat(&token::Comma) { |
| let _ = p.diagnostic().fatal("expected token `,`"); |
| } |
| |
| let tts = panictry!(p.parse_all_token_trees()); |
| p.abort_if_errors(); |
| |
| (cx_expr, tts) |
| } |
| |
| fn mk_stmts_let(cx: &ExtCtxt, sp: Span) -> Vec<ast::Stmt> { |
| // We also bind a single value, sp, to ext_cx.call_site() |
| // |
| // This causes every span in a token-tree quote to be attributed to the |
| // call site of the extension using the quote. We can't really do much |
| // better since the source of the quote may well be in a library that |
| // was not even parsed by this compilation run, that the user has no |
| // source code for (eg. in libsyntax, which they're just _using_). |
| // |
| // The old quasiquoter had an elaborate mechanism for denoting input |
| // file locations from which quotes originated; unfortunately this |
| // relied on feeding the source string of the quote back into the |
| // compiler (which we don't really want to do) and, in any case, only |
| // pushed the problem a very small step further back: an error |
| // resulting from a parse of the resulting quote is still attributed to |
| // the site the string literal occurred, which was in a source file |
| // _other_ than the one the user has control over. For example, an |
| // error in a quote from the protocol compiler, invoked in user code |
| // using macro_rules! for example, will be attributed to the macro_rules.rs |
| // file in libsyntax, which the user might not even have source to (unless |
| // they happen to have a compiler on hand). Over all, the phase distinction |
| // just makes quotes "hard to attribute". Possibly this could be fixed |
| // by recreating some of the original qq machinery in the tt regime |
| // (pushing fake FileMaps onto the parser to account for original sites |
| // of quotes, for example) but at this point it seems not likely to be |
| // worth the hassle. |
| |
| let e_sp = cx.expr_method_call(sp, |
| cx.expr_ident(sp, id_ext("ext_cx")), |
| id_ext("call_site"), |
| Vec::new()); |
| |
| let stmt_let_sp = cx.stmt_let(sp, false, |
| id_ext("_sp"), |
| e_sp); |
| |
| let stmt_let_tt = cx.stmt_let(sp, true, id_ext("tt"), cx.expr_vec_ng(sp)); |
| |
| vec!(stmt_let_sp, stmt_let_tt) |
| } |
| |
| fn statements_mk_tts(cx: &ExtCtxt, tts: &[TokenTree], matcher: bool) -> Vec<ast::Stmt> { |
| let mut ss = Vec::new(); |
| for tt in tts { |
| ss.extend(statements_mk_tt(cx, tt, matcher)); |
| } |
| ss |
| } |
| |
| fn expand_tts(cx: &ExtCtxt, sp: Span, tts: &[TokenTree]) |
| -> (P<ast::Expr>, P<ast::Expr>) { |
| let (cx_expr, tts) = parse_arguments_to_quote(cx, tts); |
| |
| let mut vector = mk_stmts_let(cx, sp); |
| vector.extend(statements_mk_tts(cx, &tts[..], false)); |
| vector.push(cx.stmt_expr(cx.expr_ident(sp, id_ext("tt")))); |
| let block = cx.expr_block(cx.block(sp, vector)); |
| |
| (cx_expr, block) |
| } |
| |
| fn expand_wrapper(cx: &ExtCtxt, |
| sp: Span, |
| cx_expr: P<ast::Expr>, |
| expr: P<ast::Expr>, |
| imports: &[&[&str]]) -> P<ast::Expr> { |
| // Explicitly borrow to avoid moving from the invoker (#16992) |
| let cx_expr_borrow = cx.expr_addr_of(sp, cx.expr_deref(sp, cx_expr)); |
| let stmt_let_ext_cx = cx.stmt_let(sp, false, id_ext("ext_cx"), cx_expr_borrow); |
| |
| let mut stmts = imports.iter().map(|path| { |
| // make item: `use ...;` |
| let path = path.iter().map(|s| s.to_string()).collect(); |
| cx.stmt_item(sp, cx.item_use_glob(sp, ast::Visibility::Inherited, ids_ext(path))) |
| }).chain(Some(stmt_let_ext_cx)).collect::<Vec<_>>(); |
| stmts.push(cx.stmt_expr(expr)); |
| |
| cx.expr_block(cx.block(sp, stmts)) |
| } |
| |
| fn expand_parse_call(cx: &ExtCtxt, |
| sp: Span, |
| parse_method: &str, |
| arg_exprs: Vec<P<ast::Expr>> , |
| tts: &[TokenTree]) -> P<ast::Expr> { |
| let (cx_expr, tts_expr) = expand_tts(cx, sp, tts); |
| |
| let cfg_call = || cx.expr_method_call( |
| sp, cx.expr_ident(sp, id_ext("ext_cx")), |
| id_ext("cfg"), Vec::new()); |
| |
| let parse_sess_call = || cx.expr_method_call( |
| sp, cx.expr_ident(sp, id_ext("ext_cx")), |
| id_ext("parse_sess"), Vec::new()); |
| |
| let new_parser_call = |
| cx.expr_call(sp, |
| cx.expr_ident(sp, id_ext("new_parser_from_tts")), |
| vec!(parse_sess_call(), cfg_call(), tts_expr)); |
| |
| let path = vec![id_ext("syntax"), id_ext("ext"), id_ext("quote"), id_ext(parse_method)]; |
| let mut args = vec![cx.expr_mut_addr_of(sp, new_parser_call)]; |
| args.extend(arg_exprs); |
| let expr = cx.expr_call_global(sp, path, args); |
| |
| if parse_method == "parse_attribute" { |
| expand_wrapper(cx, sp, cx_expr, expr, &[&["syntax", "ext", "quote", "rt"], |
| &["syntax", "parse", "attr"]]) |
| } else { |
| expand_wrapper(cx, sp, cx_expr, expr, &[&["syntax", "ext", "quote", "rt"]]) |
| } |
| } |
