auto merge of #20901 : dgrunwald/rust/update-token-can-begin-expr, r=sanxiyn

 * add `Token::AndAnd` (double borrow)
 * add `Token::DotDot` (range notation)
 * remove `Token::Pound` and `Token::At`

This fixes a syntax error when parsing `fn f() -> RangeTo<i32> { return ..1; }`.

Also, remove `fn_expr_lookahead`.
It's from the `fn~` days and seems to no longer be necessary.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/libsyntax/parse/token.rs b/src/libsyntax/parse/token.rs
index 4b3573f84c5..e5aef12e827 100644
--- a/src/libsyntax/parse/token.rs
+++ b/src/libsyntax/parse/token.rs
@@ -183,14 +183,14 @@ impl Token {
             Underscore                  => true,
             Tilde                       => true,
             Literal(_, _)               => true,
-            Pound                       => true,
-            At                          => true,
             Not                         => true,
             BinOp(Minus)                => true,
             BinOp(Star)                 => true,
             BinOp(And)                  => true,
             BinOp(Or)                   => true, // in lambda syntax
             OrOr                        => true, // in lambda syntax
+            AndAnd                      => true, // double borrow
+            DotDot                      => true, // range notation
             ModSep                      => true,
             Interpolated(NtExpr(..))    => true,
             Interpolated(NtIdent(..))   => true,