[crater] Remove LArrow

compiler/rustc_ast/src/token.rs

@@ -274,8 +274,6 @@ pub enum TokenKind {
     ModSep,
     /// `->`
     RArrow,
-    /// `<-`
-    LArrow,
     /// `=>`
     FatArrow,
     /// `#`
@@ -376,7 +374,6 @@ impl TokenKind {
             DotDotDot => (Dot, DotDot),
             ModSep => (Colon, Colon),
             RArrow => (BinOp(Minus), Gt),
-            LArrow => (Lt, BinOp(Minus)),
             FatArrow => (Eq, Gt),
             _ => return None,
         })
@@ -435,7 +432,7 @@ impl Token {
         match self.kind {
             Eq | Lt | Le | EqEq | Ne | Ge | Gt | AndAnd | OrOr | Not | Tilde | BinOp(_)
             | BinOpEq(_) | At | Dot | DotDot | DotDotDot | DotDotEq | Comma | Semi | Colon
-            | ModSep | RArrow | LArrow | FatArrow | Pound | Dollar | Question | SingleQuote => true,
+            | ModSep | RArrow | FatArrow | Pound | Dollar | Question | SingleQuote => true,
 
             OpenDelim(..) | CloseDelim(..) | Literal(..) | DocComment(..) | Ident(..)
             | Lifetime(..) | Interpolated(..) | Eof => false,
@@ -780,7 +777,6 @@ impl Token {
                 Eq => Le,
                 Lt => BinOp(Shl),
                 Le => BinOpEq(Shl),
-                BinOp(Minus) => LArrow,
                 _ => return None,
             },
             Gt => match joint.kind {
@@ -820,9 +816,9 @@ impl Token {
             },
 
             Le | EqEq | Ne | Ge | AndAnd | OrOr | Tilde | BinOpEq(..) | At | DotDotDot
-            | DotDotEq | Comma | Semi | ModSep | RArrow | LArrow | FatArrow | Pound | Dollar
-            | Question | OpenDelim(..) | CloseDelim(..) | Literal(..) | Ident(..)
-            | Lifetime(..) | Interpolated(..) | DocComment(..) | Eof => return None,
+            | DotDotEq | Comma | Semi | ModSep | RArrow | FatArrow | Pound | Dollar | Question
+            | OpenDelim(..) | CloseDelim(..) | Literal(..) | Ident(..) | Lifetime(..)
+            | Interpolated(..) | DocComment(..) | Eof => return None,
         };
 
         Some(Token::new(kind, self.span.to(joint.span)))

compiler/rustc_ast/src/util/parser.rs

@@ -94,8 +94,6 @@ impl AssocOp {
             token::DotDotEq => Some(DotDotEq),
             // DotDotDot is no longer supported, but we need some way to display the error
             token::DotDotDot => Some(DotDotEq),
-            // `<-` should probably be `< -`
-            token::LArrow => Some(Less),
             _ if t.is_keyword(kw::As) => Some(As),
             _ => None,
         }

compiler/rustc_ast_pretty/src/pprust/state.rs

@@ -758,7 +758,6 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
             token::Colon => ":".into(),
             token::ModSep => "::".into(),
             token::RArrow => "->".into(),
-            token::LArrow => "<-".into(),
             token::FatArrow => "=>".into(),
             token::OpenDelim(Delimiter::Parenthesis) => "(".into(),
             token::CloseDelim(Delimiter::Parenthesis) => ")".into(),

compiler/rustc_expand/src/proc_macro_server.rs

@@ -195,7 +195,6 @@ impl FromInternal<(TokenStream, &mut Rustc<'_, '_>)> for Vec<TokenTree<TokenStre
                 Colon => op(":"),
                 ModSep => op("::"),
                 RArrow => op("->"),
-                LArrow => op("<-"),
                 FatArrow => op("=>"),
                 Pound => op("#"),
                 Dollar => op("$"),

compiler/rustc_parse/src/parser/expr.rs

@@ -214,10 +214,6 @@ impl<'a> Parser<'a> {
                 self.err_dotdotdot_syntax(self.token.span);
             }
 
-            if self.token == token::LArrow {
-                self.err_larrow_operator(self.token.span);
-            }
-
             self.bump();
             if op.node.is_comparison() {
                 if let Some(expr) = self.check_no_chained_comparison(&lhs, &op)? {
@@ -3583,10 +3579,6 @@ impl<'a> Parser<'a> {
         self.sess.emit_err(errors::DotDotDot { span });
     }
 
-    fn err_larrow_operator(&self, span: Span) {
-        self.sess.emit_err(errors::LeftArrowOperator { span });
-    }
-
     fn mk_assign_op(&self, binop: BinOp, lhs: P<Expr>, rhs: P<Expr>) -> ExprKind {
         ExprKind::AssignOp(binop, lhs, rhs)
     }

compiler/rustc_parse/src/parser/path.rs

@@ -272,10 +272,7 @@ impl<'a> Parser<'a> {
         let is_args_start = |token: &Token| {
             matches!(
                 token.kind,
-                token::Lt
-                    | token::BinOp(token::Shl)
-                    | token::OpenDelim(Delimiter::Parenthesis)
-                    | token::LArrow
+                token::Lt | token::BinOp(token::Shl) | token::OpenDelim(Delimiter::Parenthesis)
             )
         };
         let check_args_start = |this: &mut Self| {