Skip to content

Commit

Permalink
Rollup merge of rust-lang#41946 - qnighy:disallow-dot-underscore-in-f…
Browse files Browse the repository at this point in the history
…loat, r=petrochenkov

Disallow ._ in float literal.

This patch makes lexer stop parsing number literals before `._`, as well as before `.a`. Underscore itself is still allowed like in `4_000_000.000_000_`.

Fixes a half part of rust-lang#41723. The other is `""_`.
  • Loading branch information
frewsxcv authored May 13, 2017
2 parents 08d99c5 + 7b535e1 commit 8755896
Show file tree
Hide file tree
Showing 3 changed files with 33 additions and 3 deletions.
4 changes: 1 addition & 3 deletions src/libsyntax/parse/lexer/mod.rs
Original file line number Diff line number Diff line change
Expand Up @@ -754,9 +754,7 @@ impl<'a> StringReader<'a> {
// integer literal followed by field/method access or a range pattern
// (`0..2` and `12.foo()`)
if self.ch_is('.') && !self.nextch_is('.') &&
!self.nextch()
.unwrap_or('\0')
.is_xid_start() {
!ident_start(self.nextch()) {
// might have stuff after the ., and if it does, it needs to start
// with a number
self.bump();
Expand Down
13 changes: 13 additions & 0 deletions src/test/parse-fail/underscore-suffix-for-float.rs
Original file line number Diff line number Diff line change
@@ -0,0 +1,13 @@
// Copyright 2017 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.

fn main() {
let a = 42._; //~ ERROR unexpected token: `_`
}
19 changes: 19 additions & 0 deletions src/test/run-pass/underscore-method-after-integer.rs
Original file line number Diff line number Diff line change
@@ -0,0 +1,19 @@
// Copyright 2017 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.

trait Tr : Sized {
fn _method_on_numbers(self) {}
}

impl Tr for i32 {}

fn main() {
42._method_on_numbers();
}

0 comments on commit 8755896

Please sign in to comment.