get rid of prec.rs

prec.rs no longer had much to do with precedence; the token->binop
function fits better in token.rs, and the one-liner defining the
precedence of 'as' can go next to the other precedence stuff in
ast_util.rs

Author: jbclements

src/libsyntax/ast_util.rs

@@ -355,6 +355,10 @@ pub fn operator_prec(op: ast::binop) -> uint {
   }
 }
 
+/// Precedence of the `as` operator, which is a binary operator
+/// not appearing in the prior table.
+pub static as_prec: uint = 11u;
+
 pub fn dtor_ty() -> @ast::Ty {
     @ast::Ty {id: 0, node: ty_nil, span: dummy_sp()}
 }

src/libsyntax/parse/mod.rs

@@ -36,9 +36,6 @@ pub mod attr;
 /// Common routines shared by parser mods
 pub mod common;
 
-/// Functions dealing with operator precedence
-pub mod prec;
-
 /// Routines the parser uses to classify AST nodes
 pub mod classify;
 

src/libsyntax/parse/parser.rs

@@ -58,7 +58,7 @@ use ast::{view_item_, view_item_extern_mod, view_item_use};
 use ast::{view_path, view_path_glob, view_path_list, view_path_simple};
 use ast::visibility;
 use ast;
-use ast_util::{ident_to_path, operator_prec};
+use ast_util::{as_prec, ident_to_path, operator_prec};
 use ast_util;
 use codemap::{span, BytePos, spanned, mk_sp};
 use codemap;
@@ -82,9 +82,8 @@ use parse::obsolete::ObsoleteMode;
 use parse::obsolete::{ObsoleteLifetimeNotation, ObsoleteConstManagedPointer};
 use parse::obsolete::{ObsoletePurity, ObsoleteStaticMethod};
 use parse::obsolete::{ObsoleteConstItem, ObsoleteFixedLengthVectorType};
-use parse::prec::{as_prec, token_to_binop};
 use parse::token::{can_begin_expr, is_ident, is_ident_or_path};
-use parse::token::{is_plain_ident, INTERPOLATED, special_idents};
+use parse::token::{is_plain_ident, INTERPOLATED, special_idents, token_to_binop};
 use parse::token;
 use parse::{new_sub_parser_from_file, next_node_id, ParseSess};
 use opt_vec;

src/libsyntax/parse/prec.rs

@@ -364,6 +364,34 @@ impl<'self> to_bytes::IterBytes for StringRef<'self> {
     }
 }
 
+/**
+ * Maps a token to a record specifying the corresponding binary
+ * operator
+ */
+pub fn token_to_binop(tok: Token) -> Option<ast::binop> {
+  match tok {
+      BINOP(STAR)    => Some(ast::mul),
+      BINOP(SLASH)   => Some(ast::quot),
+      BINOP(PERCENT) => Some(ast::rem),
+      BINOP(PLUS)    => Some(ast::add),
+      BINOP(MINUS)   => Some(ast::subtract),
+      BINOP(SHL)     => Some(ast::shl),
+      BINOP(SHR)     => Some(ast::shr),
+      BINOP(AND)     => Some(ast::bitand),
+      BINOP(CARET)   => Some(ast::bitxor),
+      BINOP(OR)      => Some(ast::bitor),
+      LT             => Some(ast::lt),
+      LE             => Some(ast::le),
+      GE             => Some(ast::ge),
+      GT             => Some(ast::gt),
+      EQEQ           => Some(ast::eq),
+      NE             => Some(ast::ne),
+      ANDAND         => Some(ast::and),
+      OROR           => Some(ast::or),
+      _              => None
+  }
+}
+
 pub struct ident_interner {
     priv interner: Interner<@~str>,
 }