diff options
| -rw-r--r-- | src/libsyntax/parse/token.rs | 24 | ||||
| -rw-r--r-- | src/test/compile-fail/can-begin-expr-check.rs | 30 |
2 files changed, 53 insertions, 1 deletions
diff --git a/src/libsyntax/parse/token.rs b/src/libsyntax/parse/token.rs index bf790b96e37..43ad1eacf33 100644 --- a/src/libsyntax/parse/token.rs +++ b/src/libsyntax/parse/token.rs @@ -80,6 +80,28 @@ impl Lit { } } +fn ident_can_begin_expr(ident: ast::Ident) -> bool { + let ident_token: Token = Ident(ident); + + !ident_token.is_any_keyword() || + ident_token.is_path_segment_keyword() || + [ + keywords::Box.name(), + keywords::Break.name(), + keywords::Continue.name(), + keywords::False.name(), + keywords::For.name(), + keywords::If.name(), + keywords::Loop.name(), + keywords::Match.name(), + keywords::Move.name(), + keywords::Return.name(), + keywords::True.name(), + keywords::Unsafe.name(), + keywords::While.name(), + ].contains(&ident.name) +} + #[derive(Clone, RustcEncodable, RustcDecodable, PartialEq, Eq, Hash, Debug)] pub enum Token { /* Expression-operator symbols. */ @@ -163,7 +185,7 @@ impl Token { pub fn can_begin_expr(&self) -> bool { match *self { OpenDelim(..) => true, - Ident(..) => true, + Ident(ident) => ident_can_begin_expr(ident), Literal(..) => true, Not => true, BinOp(Minus) => true, diff --git a/src/test/compile-fail/can-begin-expr-check.rs b/src/test/compile-fail/can-begin-expr-check.rs new file mode 100644 index 00000000000..68f219c6ed9 --- /dev/null +++ b/src/test/compile-fail/can-begin-expr-check.rs @@ -0,0 +1,30 @@ +// Copyright 2014 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. + +pub fn main() { + + return; + return (); + return as (); + return return as (); + return return return; + + return if true { + () + } else { + () + }; + + loop { + return break as (); + } + + return enum; //~ ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `enum` +} |