libsyntax: Remove the restricted keyword concept

src/libsyntax/parse/common.rs

@@ -37,9 +37,6 @@ trait parser_common {
     fn is_any_keyword(tok: token::token) -> bool;
     fn eat_keyword(word: ~str) -> bool;
     fn expect_keyword(word: ~str);
-    fn is_restricted_keyword(word: ~str) -> bool;
-    fn check_restricted_keywords();
-    fn check_restricted_keywords_(w: ~str);
     fn expect_gt();
     fn parse_seq_to_before_gt<T: Copy>(sep: Option<token::token>,
                                        f: fn(parser) -> T) -> ~[T];
@@ -104,7 +101,6 @@ impl parser: parser_common {
     }
 
     fn parse_value_ident() -> ast::ident {
-        self.check_restricted_keywords();
         return self.parse_ident();
     }
 
@@ -165,26 +161,6 @@ impl parser: parser_common {
         }
     }
 
-    fn is_restricted_keyword(word: ~str) -> bool {
-        self.restricted_keywords.contains_key_ref(&word)
-    }
-
-    fn check_restricted_keywords() {
-        match self.token {
-          token::IDENT(_, false) => {
-            let w = token_to_str(self.reader, self.token);
-            self.check_restricted_keywords_(w);
-          }
-          _ => ()
-        }
-    }
-
-    fn check_restricted_keywords_(w: ~str) {
-        if self.is_restricted_keyword(w) {
-            self.fatal(~"found `" + w + ~"` in restricted position");
-        }
-    }
-
     fn is_strict_keyword(word: ~str) -> bool {
         self.strict_keywords.contains_key_ref(&word)
     }

src/libsyntax/parse/parser.rs

@@ -217,7 +217,6 @@ fn parser(sess: parse_sess, cfg: ast::crate_cfg,
         restriction: UNRESTRICTED,
         quote_depth: 0u,
         keywords: token::keyword_table(),
-        restricted_keywords: token::restricted_keyword_table(),
         strict_keywords: token::strict_keyword_table(),
         reserved_keywords: token::reserved_keyword_table(),
         obsolete_set: std::map::HashMap(),
@@ -239,7 +238,6 @@ struct parser {
     reader: reader,
     interner: interner<@~str>,
     keywords: HashMap<~str, ()>,
-    restricted_keywords: HashMap<~str, ()>,
     strict_keywords: HashMap<~str, ()>,
     reserved_keywords: HashMap<~str, ()>,
     /// The set of seen errors about obsolete syntax. Used to suppress
@@ -3200,7 +3198,6 @@ impl parser {
         let ty_params = self.parse_ty_params();
         // Newtype syntax
         if self.token == token::EQ {
-            self.check_restricted_keywords_(*self.id_to_str(id));
             self.bump();
             let ty = self.parse_ty(false);
             self.expect(token::SEMI);

src/libsyntax/parse/token.rs

@@ -362,20 +362,17 @@ fn mk_fake_ident_interner() -> ident_interner {
 /**
  * All the valid words that have meaning in the Rust language.
  *
- * Rust keywords are either 'temporary', 'restricted', or 'strict'.  Temporary
+ * Rust keywords are either 'temporary', 'strict' or 'reserved'.  Temporary
  * keywords are contextual and may be used as identifiers anywhere.  They are
- * expected to disappear from the grammar soon.  Restricted keywords may not
- * appear in positions that might otherwise contain _value identifiers_.
- * Strict keywords may not appear as identifiers at all.
+ * expected to disappear from the grammar soon.  Strict keywords may not
+ * appear as identifiers at all. Reserved keywords are not used anywhere in
+ * the language and may not appear as identifiers.
  */
 fn keyword_table() -> HashMap<~str, ()> {
     let keywords = str_hash();
     for temporary_keyword_table().each_key |word| {
         keywords.insert(word, ());
     }
-    for restricted_keyword_table().each_key |word| {
-        keywords.insert(word, ());
-    }
     for strict_keyword_table().each_key |word| {
         keywords.insert(word, ());
     }
@@ -397,30 +394,6 @@ fn temporary_keyword_table() -> HashMap<~str, ()> {
     words
 }
 
-/**
- * Keywords that may not appear in any position that might otherwise contain a
- * _value identifier_. Restricted keywords may still be used as other types of
- * identifiers.
- *
- * Reasons:
- *
- * * For some (most?), if used at the start of a line, they will cause the
- *   line to be interpreted as a specific kind of statement, which would be
- *   confusing.
- *
- * * `true` or `false` as identifiers would always be shadowed by
- *   the boolean constants
- */
-fn restricted_keyword_table() -> HashMap<~str, ()> {
-    let words = str_hash();
-    let keys = ~[
-    ];
-    for keys.each |word| {
-        words.insert(word, ());
-    }
-    words
-}
-
 /// Full keywords. May not appear anywhere else.
 fn strict_keyword_table() -> HashMap<~str, ()> {
     let words = str_hash();