Make the parser more careful about keywords

Keywords are now only recognized in contexts where they are valid. The
lexer no longer recognizes them, all words are lexed as IDENT tokens,
that get interpreted by the parser.

Author: marijnh

src/comp/front/lexer.rs

@@ -22,8 +22,6 @@ state type reader = state obj {
     fn add_str(str) -> token::str_num;
     fn get_str(token::str_num) -> str;
     fn get_chpos() -> uint;
-    fn get_keywords() -> hashmap[str,token::token];
-    fn get_reserved() -> hashmap[str,()];
     fn get_filemap() -> codemap::filemap;
     fn err(str m);
 };
@@ -39,8 +37,6 @@ fn new_reader(session sess, io::reader rdr,
                      mutable uint mark_chpos,
                      mutable uint chpos,
                      mutable vec[str] strs,
-                     hashmap[str,token::token] keywords,
-                     hashmap[str,()] reserved,
                      codemap::filemap fm) {
 
         fn is_eof() -> bool {
@@ -82,10 +78,6 @@ fn new_reader(session sess, io::reader rdr,
             }
         }
 
-        fn get_keywords() -> hashmap[str,token::token] {
-            ret keywords;
-        }
-
         fn add_str(str s) -> token::str_num {
             strs += vec(s);
             ret _vec::len[str](strs) - 1u;
@@ -95,10 +87,6 @@ fn new_reader(session sess, io::reader rdr,
             ret strs.(i);
         }
 
-        fn get_reserved() -> hashmap[str,()] {
-            ret reserved;
-        }
-
         fn get_filemap() -> codemap::filemap {
             ret fm;
         }
@@ -111,133 +99,11 @@ fn new_reader(session sess, io::reader rdr,
     let vec[str] strs = vec();
     auto rd = reader(sess, file, _str::byte_len(file), 0u, -1 as char,
                      filemap.start_pos, filemap.start_pos,
-                     strs, keyword_table(),
-                     reserved_word_table(),
-                     filemap);
+                     strs, filemap);
     rd.init();
     ret rd;
 }
 
-fn keyword_table() -> std::map::hashmap[str, token::token] {
-    auto keywords = new_str_hash[token::token]();
-
-    keywords.insert("mod", token::MOD);
-    keywords.insert("use", token::USE);
-    keywords.insert("meta", token::META);
-    keywords.insert("auth", token::AUTH);
-
-    keywords.insert("syntax", token::SYNTAX);
-
-    keywords.insert("if", token::IF);
-    keywords.insert("else", token::ELSE);
-    keywords.insert("while", token::WHILE);
-    keywords.insert("do", token::DO);
-    keywords.insert("alt", token::ALT);
-    keywords.insert("case", token::CASE);
-
-    keywords.insert("for", token::FOR);
-    keywords.insert("each", token::EACH);
-    keywords.insert("break", token::BREAK);
-    keywords.insert("cont", token::CONT);
-    keywords.insert("put", token::PUT);
-    keywords.insert("ret", token::RET);
-    keywords.insert("be", token::BE);
-
-    keywords.insert("fail", token::FAIL);
-    keywords.insert("drop", token::DROP);
-
-    keywords.insert("type", token::TYPE);
-    keywords.insert("check", token::CHECK);
-    keywords.insert("assert", token::ASSERT);
-    keywords.insert("claim", token::CLAIM);
-    keywords.insert("prove", token::PROVE);
-
-    keywords.insert("state", token::STATE);
-    keywords.insert("gc", token::GC);
-
-    keywords.insert("unsafe", token::UNSAFE);
-
-    keywords.insert("native", token::NATIVE);
-    keywords.insert("mutable", token::MUTABLE);
-    keywords.insert("auto", token::AUTO);
-
-    keywords.insert("fn", token::FN);
-    keywords.insert("pred", token::PRED);
-    keywords.insert("iter", token::ITER);
-
-    keywords.insert("import", token::IMPORT);
-    keywords.insert("export", token::EXPORT);
-
-    keywords.insert("let", token::LET);
-    keywords.insert("const", token::CONST);
-
-    keywords.insert("log", token::LOG);
-    keywords.insert("log_err", token::LOG_ERR);
-    keywords.insert("spawn", token::SPAWN);
-    keywords.insert("thread", token::THREAD);
-    keywords.insert("yield", token::YIELD);
-    keywords.insert("join", token::JOIN);
-
-    keywords.insert("bool", token::BOOL);
-
-    keywords.insert("int", token::INT);
-    keywords.insert("uint", token::UINT);
-    keywords.insert("float", token::FLOAT);
-
-    keywords.insert("char", token::CHAR);
-    keywords.insert("str", token::STR);
-
-
-    keywords.insert("rec", token::REC);
-    keywords.insert("tup", token::TUP);
-    keywords.insert("tag", token::TAG);
-    keywords.insert("vec", token::VEC);
-    keywords.insert("any", token::ANY);
-
-    keywords.insert("obj", token::OBJ);
-    keywords.insert("self", token::SELF);
-
-    keywords.insert("port", token::PORT);
-    keywords.insert("chan", token::CHAN);
-
-    keywords.insert("task", token::TASK);
-
-    keywords.insert("true", token::LIT_BOOL(true));
-    keywords.insert("false", token::LIT_BOOL(false));
-
-    keywords.insert("in", token::IN);
-
-    keywords.insert("as", token::AS);
-    keywords.insert("with", token::WITH);
-
-    keywords.insert("bind", token::BIND);
-
-    keywords.insert("u8", token::MACH(common::ty_u8));
-    keywords.insert("u16", token::MACH(common::ty_u16));
-    keywords.insert("u32", token::MACH(common::ty_u32));
-    keywords.insert("u64", token::MACH(common::ty_u64));
-    keywords.insert("i8", token::MACH(common::ty_i8));
-    keywords.insert("i16", token::MACH(common::ty_i16));
-    keywords.insert("i32", token::MACH(common::ty_i32));
-    keywords.insert("i64", token::MACH(common::ty_i64));
-    keywords.insert("f32", token::MACH(common::ty_f32));
-    keywords.insert("f64", token::MACH(common::ty_f64));
-
-    ret keywords;
-}
-
-fn reserved_word_table() -> std::map::hashmap[str, ()] {
-    auto reserved = new_str_hash[()]();
-    reserved.insert("f16", ());  // IEEE 754-2008 'binary16' interchange fmt
-    reserved.insert("f80", ());  // IEEE 754-1985 'extended'
-    reserved.insert("f128", ()); // IEEE 754-2008 'binary128'
-    reserved.insert("m32", ());  // IEEE 754-2008 'decimal32'
-    reserved.insert("m64", ());  // IEEE 754-2008 'decimal64'
-    reserved.insert("m128", ()); // IEEE 754-2008 'decimal128'
-    reserved.insert("dec", ());  // One of m32, m64, m128
-    ret reserved;
-}
-
 fn in_range(char c, char lo, char hi) -> bool {
     ret lo <= c && c <= hi;
 }
@@ -604,17 +470,6 @@ fn next_token(reader rdr) -> token::token {
             ret token::UNDERSCORE;
         }
 
-        auto kwds = rdr.get_keywords();
-        if (kwds.contains_key(accum_str)) {
-            ret kwds.get(accum_str);
-        }
-
-        auto rsvd = rdr.get_reserved();
-        if (rsvd.contains_key(accum_str)) {
-            rdr.err(#fmt("reserved keyword: %s", accum_str));
-            fail;
-        }
-
         ret token::IDENT(rdr.add_str(accum_str));
     }