auto merge of #19118 : jakub-/rust/roll-up, r=jakub-

4 files changed, 288 insertions, 223 deletions

diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs
index 01a66243a96..fbca4868255 100644
--- a/src/libsyntax/parse/lexer/mod.rs
+++ b/src/libsyntax/parse/lexer/mod.rs
@@ -369,6 +369,25 @@ impl<'a> StringReader<'a> {
         self.nextnextch() == Some(c)
     }
 
+    /// Eats <XID_start><XID_continue>*, if possible.
+    fn scan_optional_raw_name(&mut self) -> Option<ast::Name> {
+        if !ident_start(self.curr) {
+            return None
+        }
+        let start = self.last_pos;
+        while ident_continue(self.curr) {
+            self.bump();
+        }
+
+        self.with_str_from(start, |string| {
+            if string == "_" {
+                None
+            } else {
+                Some(token::intern(string))
+            }
+        })
+    }
+
     /// PRECONDITION: self.curr is not whitespace
     /// Eats any kind of comment.
     fn scan_comment(&mut self) -> Option<TokenAndSpan> {
@@ -638,7 +657,7 @@ impl<'a> StringReader<'a> {
     }
 
     /// Lex a LIT_INTEGER or a LIT_FLOAT
-    fn scan_number(&mut self, c: char) -> token::Token {
+    fn scan_number(&mut self, c: char) -> token::Lit {
         let mut num_digits;
         let mut base = 10;
         let start_bpos = self.last_pos;
@@ -653,19 +672,9 @@ impl<'a> StringReader<'a> {
                 '0'...'9' | '_' | '.' => {
                     num_digits = self.scan_digits(10) + 1;
                 }
-                'u' | 'i' => {
-                    self.scan_int_suffix();
-                    return token::LitInteger(self.name_from(start_bpos));
-                },
-                'f' => {
-                    let last_pos = self.last_pos;
-                    self.scan_float_suffix();
-                    self.check_float_base(start_bpos, last_pos, base);
-                    return token::LitFloat(self.name_from(start_bpos));
-                }
                 _ => {
                     // just a 0
-                    return token::LitInteger(self.name_from(start_bpos));
+                    return token::Integer(self.name_from(start_bpos));
                 }
             }
         } else if c.is_digit_radix(10) {
@@ -676,9 +685,7 @@ impl<'a> StringReader<'a> {
 
         if num_digits == 0 {
             self.err_span_(start_bpos, self.last_pos, "no valid digits found for number");
-            // eat any suffix
-            self.scan_int_suffix();
-            return token::LitInteger(token::intern("0"));
+            return token::Integer(token::intern("0"));
         }
 
         // might be a float, but don't be greedy if this is actually an
@@ -692,29 +699,20 @@ impl<'a> StringReader<'a> {
             if self.curr.unwrap_or('\0').is_digit_radix(10) {
                 self.scan_digits(10);
                 self.scan_float_exponent();
-                self.scan_float_suffix();
             }
             let last_pos = self.last_pos;
             self.check_float_base(start_bpos, last_pos, base);
-            return token::LitFloat(self.name_from(start_bpos));
-        } else if self.curr_is('f') {
-            // or it might be an integer literal suffixed as a float
-            self.scan_float_suffix();
-            let last_pos = self.last_pos;
-            self.check_float_base(start_bpos, last_pos, base);
-            return token::LitFloat(self.name_from(start_bpos));
+            return token::Float(self.name_from(start_bpos));
         } else {
             // it might be a float if it has an exponent
             if self.curr_is('e') || self.curr_is('E') {
                 self.scan_float_exponent();
-                self.scan_float_suffix();
                 let last_pos = self.last_pos;
                 self.check_float_base(start_bpos, last_pos, base);
-                return token::LitFloat(self.name_from(start_bpos));
+                return token::Float(self.name_from(start_bpos));
             }
             // but we certainly have an integer!
-            self.scan_int_suffix();
-            return token::LitInteger(self.name_from(start_bpos));
+            return token::Integer(self.name_from(start_bpos));
         }
     }
 
@@ -850,55 +848,6 @@ impl<'a> StringReader<'a> {
         true
     }
 
-    /// Scan over an int literal suffix.
-    fn scan_int_suffix(&mut self) {
-        match self.curr {
-            Some('i') | Some('u') => {
-                self.bump();
-
-                if self.curr_is('8') {
-                    self.bump();
-                } else if self.curr_is('1') {
-                    if !self.nextch_is('6') {
-                        self.err_span_(self.last_pos, self.pos,
-                                      "illegal int suffix");
-                    } else {
-                        self.bump(); self.bump();
-                    }
-                } else if self.curr_is('3') {
-                    if !self.nextch_is('2') {
-                        self.err_span_(self.last_pos, self.pos,
-                                      "illegal int suffix");
-                    } else {
-                        self.bump(); self.bump();
-                    }
-                } else if self.curr_is('6') {
-                    if !self.nextch_is('4') {
-                        self.err_span_(self.last_pos, self.pos,
-                                      "illegal int suffix");
-                    } else {
-                        self.bump(); self.bump();
-                    }
-                }
-            },
-            _ => { }
-        }
-    }
-
-    /// Scan over a float literal suffix
-    fn scan_float_suffix(&mut self) {
-        if self.curr_is('f') {
-            if (self.nextch_is('3') && self.nextnextch_is('2'))
-            || (self.nextch_is('6') && self.nextnextch_is('4')) {
-                self.bump();
-                self.bump();
-                self.bump();
-            } else {
-                self.err_span_(self.last_pos, self.pos, "illegal float suffix");
-            }
-        }
-    }
-
     /// Scan over a float exponent.
     fn scan_float_exponent(&mut self) {
         if self.curr_is('e') || self.curr_is('E') {
@@ -967,7 +916,10 @@ impl<'a> StringReader<'a> {
         }
 
         if is_dec_digit(c) {
-            return self.scan_number(c.unwrap());
+            let num = self.scan_number(c.unwrap());
+            let suffix = self.scan_optional_raw_name();
+            debug!("next_token_inner: scanned number {}, {}", num, suffix);
+            return token::Literal(num, suffix)
         }
 
         if self.read_embedded_ident {
@@ -1126,17 +1078,19 @@ impl<'a> StringReader<'a> {
             }
             let id = if valid { self.name_from(start) } else { token::intern("0") };
             self.bump(); // advance curr past token
-            return token::LitChar(id);
+            let suffix = self.scan_optional_raw_name();
+            return token::Literal(token::Char(id), suffix);
           }
           'b' => {
             self.bump();
-            return match self.curr {
+            let lit = match self.curr {
                 Some('\'') => self.scan_byte(),
                 Some('"') => self.scan_byte_string(),
                 Some('r') => self.scan_raw_byte_string(),
                 _ => unreachable!()  // Should have been a token::Ident above.
             };
-
+            let suffix = self.scan_optional_raw_name();
+            return token::Literal(lit, suffix);
           }
           '"' => {
             let start_bpos = self.last_pos;
@@ -1157,7 +1111,8 @@ impl<'a> StringReader<'a> {
             let id = if valid { self.name_from(start_bpos + BytePos(1)) }
                      else { token::intern("??") };
             self.bump();
-            return token::LitStr(id);
+            let suffix = self.scan_optional_raw_name();
+            return token::Literal(token::Str_(id), suffix);
           }
           'r' => {
             let start_bpos = self.last_pos;
@@ -1224,7 +1179,8 @@ impl<'a> StringReader<'a> {
             } else {
                 token::intern("??")
             };
-            return token::LitStrRaw(id, hash_count);
+            let suffix = self.scan_optional_raw_name();
+            return token::Literal(token::StrRaw(id, hash_count), suffix);
           }
           '-' => {
             if self.nextch_is('>') {
@@ -1293,7 +1249,7 @@ impl<'a> StringReader<'a> {
      || (self.curr_is('#') && self.nextch_is('!') && !self.nextnextch_is('['))
     }
 
-    fn scan_byte(&mut self) -> token::Token {
+    fn scan_byte(&mut self) -> token::Lit {
         self.bump();
         let start = self.last_pos;
 
@@ -1314,10 +1270,10 @@ impl<'a> StringReader<'a> {
 
         let id = if valid { self.name_from(start) } else { token::intern("??") };
         self.bump(); // advance curr past token
-        return token::LitByte(id);
+        return token::Byte(id);
     }
 
-    fn scan_byte_string(&mut self) -> token::Token {
+    fn scan_byte_string(&mut self) -> token::Lit {
         self.bump();
         let start = self.last_pos;
         let mut valid = true;
@@ -1336,10 +1292,10 @@ impl<'a> StringReader<'a> {
         }
         let id = if valid { self.name_from(start) } else { token::intern("??") };
         self.bump();
-        return token::LitBinary(id);
+        return token::Binary(id);
     }
 
-    fn scan_raw_byte_string(&mut self) -> token::Token {
+    fn scan_raw_byte_string(&mut self) -> token::Lit {
         let start_bpos = self.last_pos;
         self.bump();
         let mut hash_count = 0u;
@@ -1387,8 +1343,9 @@ impl<'a> StringReader<'a> {
             self.bump();
         }
         self.bump();
-        return token::LitBinaryRaw(self.name_from_to(content_start_bpos, content_end_bpos),
-                                     hash_count);
+        return token::BinaryRaw(self.name_from_to(content_start_bpos,
+                                                  content_end_bpos),
+                                hash_count);
     }
 }
 
@@ -1535,17 +1492,17 @@ mod test {
 
     #[test] fn character_a() {
         assert_eq!(setup(&mk_sh(), "'a'".to_string()).next_token().tok,
-                   token::LitChar(token::intern("a")));
+                   token::Literal(token::Char(token::intern("a")), None));
     }
 
     #[test] fn character_space() {
         assert_eq!(setup(&mk_sh(), "' '".to_string()).next_token().tok,
-                   token::LitChar(token::intern(" ")));
+                   token::Literal(token::Char(token::intern(" ")), None));
     }
 
     #[test] fn character_escaped() {
         assert_eq!(setup(&mk_sh(), "'\\n'".to_string()).next_token().tok,
-                   token::LitChar(token::intern("\\n")));
+                   token::Literal(token::Char(token::intern("\\n")), None));
     }
 
     #[test] fn lifetime_name() {
@@ -1557,7 +1514,41 @@ mod test {
         assert_eq!(setup(&mk_sh(),
                          "r###\"\"#a\\b\x00c\"\"###".to_string()).next_token()
                                                                  .tok,
-                   token::LitStrRaw(token::intern("\"#a\\b\x00c\""), 3));
+                   token::Literal(token::StrRaw(token::intern("\"#a\\b\x00c\""), 3), None));
+    }
+
+    #[test] fn literal_suffixes() {
+        macro_rules! test {
+            ($input: expr, $tok_type: ident, $tok_contents: expr) => {{
+                assert_eq!(setup(&mk_sh(), format!("{}suffix", $input)).next_token().tok,
+                           token::Literal(token::$tok_type(token::intern($tok_contents)),
+                                          Some(token::intern("suffix"))));
+                // with a whitespace separator:
+                assert_eq!(setup(&mk_sh(), format!("{} suffix", $input)).next_token().tok,
+                           token::Literal(token::$tok_type(token::intern($tok_contents)),
+                                          None));
+            }}
+        }
+
+        test!("'a'", Char, "a");
+        test!("b'a'", Byte, "a");
+        test!("\"a\"", Str_, "a");
+        test!("b\"a\"", Binary, "a");
+        test!("1234", Integer, "1234");
+        test!("0b101", Integer, "0b101");
+        test!("0xABC", Integer, "0xABC");
+        test!("1.0", Float, "1.0");
+        test!("1.0e10", Float, "1.0e10");
+
+        assert_eq!(setup(&mk_sh(), "2u".to_string()).next_token().tok,
+                   token::Literal(token::Integer(token::intern("2")),
+                                  Some(token::intern("u"))));
+        assert_eq!(setup(&mk_sh(), "r###\"raw\"###suffix".to_string()).next_token().tok,
+                   token::Literal(token::StrRaw(token::intern("raw"), 3),
+                                  Some(token::intern("suffix"))));
+        assert_eq!(setup(&mk_sh(), "br###\"raw\"###suffix".to_string()).next_token().tok,
+                   token::Literal(token::BinaryRaw(token::intern("raw"), 3),
+                                  Some(token::intern("suffix"))));
     }
 
     #[test] fn line_doc_comments() {
@@ -1573,7 +1564,7 @@ mod test {
             token::Comment => { },
             _ => panic!("expected a comment!")
         }
-        assert_eq!(lexer.next_token().tok, token::LitChar(token::intern("a")));
+        assert_eq!(lexer.next_token().tok, token::Literal(token::Char(token::intern("a")), None));
     }
 
 }
diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index 3ce49b9d7a3..96659031e6a 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -511,28 +511,41 @@ pub fn raw_str_lit(lit: &str) -> String {
     res
 }
 
-pub fn float_lit(s: &str) -> ast::Lit_ {
-    debug!("float_lit: {}", s);
-    // FIXME #2252: bounds checking float literals is defered until trans
-    let s2 = s.chars().filter(|&c| c != '_').collect::<String>();
-    let s = s2.as_slice();
-
-    let mut ty = None;
-
-    if s.ends_with("f32") {
-        ty = Some(ast::TyF32);
-    } else if s.ends_with("f64") {
-        ty = Some(ast::TyF64);
-    }
+// check if `s` looks like i32 or u1234 etc.
+fn looks_like_width_suffix(first_chars: &[char], s: &str) -> bool {
+    s.len() > 1 &&
+        first_chars.contains(&s.char_at(0)) &&
+        s.slice_from(1).chars().all(|c| '0' <= c && c <= '9')
+}
 
+fn filtered_float_lit(data: token::InternedString, suffix: Option<&str>,
+                      sd: &SpanHandler, sp: Span) -> ast::Lit_ {
+    debug!("filtered_float_lit: {}, {}", data, suffix);
+    match suffix {
+        Some("f32") => ast::LitFloat(data, ast::TyF32),
+        Some("f64") => ast::LitFloat(data, ast::TyF64),
+        Some(suf) => {
+            if suf.len() >= 2 && looks_like_width_suffix(&['f'], suf) {
+                // if it looks like a width, lets try to be helpful.
+                sd.span_err(sp, &*format!("illegal width `{}` for float literal, \
+                                          valid widths are 32 and 64", suf.slice_from(1)));
+            } else {
+                sd.span_err(sp, &*format!("illegal suffix `{}` for float literal, \
+                                          valid suffixes are `f32` and `f64`", suf));
+            }
 
-    match ty {
-        Some(t) => {
-            ast::LitFloat(token::intern_and_get_ident(s.slice_to(s.len() - t.suffix_len())), t)
-        },
-        None => ast::LitFloatUnsuffixed(token::intern_and_get_ident(s))
+            ast::LitFloatUnsuffixed(data)
+        }
+        None => ast::LitFloatUnsuffixed(data)
     }
 }
+pub fn float_lit(s: &str, suffix: Option<&str>, sd: &SpanHandler, sp: Span) -> ast::Lit_ {
+    debug!("float_lit: {}, {}", s, suffix);
+    // FIXME #2252: bounds checking float literals is defered until trans
+    let s = s.chars().filter(|&c| c != '_').collect::<String>();
+    let data = token::intern_and_get_ident(&*s);
+    filtered_float_lit(data, suffix, sd, sp)
+}
 
 /// Parse a string representing a byte literal into its final form. Similar to `char_lit`
 pub fn byte_lit(lit: &str) -> (u8, uint) {
@@ -626,24 +639,19 @@ pub fn binary_lit(lit: &str) -> Rc<Vec<u8>> {
     Rc::new(res)
 }
 
-pub fn integer_lit(s: &str, sd: &SpanHandler, sp: Span) -> ast::Lit_ {
+pub fn integer_lit(s: &str, suffix: Option<&str>, sd: &SpanHandler, sp: Span) -> ast::Lit_ {
     // s can only be ascii, byte indexing is fine
 
     let s2 = s.chars().filter(|&c| c != '_').collect::<String>();
     let mut s = s2.as_slice();
 
-    debug!("parse_integer_lit: {}", s);
-
-    if s.len() == 1 {
-        let n = (s.char_at(0)).to_digit(10).unwrap();
-        return ast::LitInt(n as u64, ast::UnsuffixedIntLit(ast::Sign::new(n)));
-    }
+    debug!("integer_lit: {}, {}", s, suffix);
 
     let mut base = 10;
     let orig = s;
     let mut ty = ast::UnsuffixedIntLit(ast::Plus);
 
-    if s.char_at(0) == '0' {
+    if s.char_at(0) == '0' && s.len() > 1 {
         match s.char_at(1) {
             'x' => base = 16,
             'o' => base = 8,
@@ -652,57 +660,56 @@ pub fn integer_lit(s: &str, sd: &SpanHandler, sp: Span) -> ast::Lit_ {
         }
     }
 
+    // 1f64 and 2f32 etc. are valid float literals.
+    match suffix {
+        Some(suf) if looks_like_width_suffix(&['f'], suf) => {
+            match base {
+                16u => sd.span_err(sp, "hexadecimal float literal is not supported"),
+                8u => sd.span_err(sp, "octal float literal is not supported"),
+                2u => sd.span_err(sp, "binary float literal is not supported"),
+                _ => ()
+            }
+            let ident = token::intern_and_get_ident(&*s);
+            return filtered_float_lit(ident, suffix, sd, sp)
+        }
+        _ => {}
+    }
+
     if base != 10 {
         s = s.slice_from(2);
     }
 
-    let last = s.len() - 1;
-    match s.char_at(last) {
-        'i' => ty = ast::SignedIntLit(ast::TyI, ast::Plus),
-        'u' => ty = ast::UnsignedIntLit(ast::TyU),
-        '8' => {
-            if s.len() > 2 {
-                match s.char_at(last - 1) {
-                    'i' => ty = ast::SignedIntLit(ast::TyI8, ast::Plus),
-                    'u' => ty = ast::UnsignedIntLit(ast::TyU8),
-                    _ => { }
-                }
-            }
-        },
-        '6' => {
-            if s.len() > 3 && s.char_at(last - 1) == '1' {
-                match s.char_at(last - 2) {
-                    'i' => ty = ast::SignedIntLit(ast::TyI16, ast::Plus),
-                    'u' => ty = ast::UnsignedIntLit(ast::TyU16),
-                    _ => { }
-                }
-            }
-        },
-        '2' => {
-            if s.len() > 3 && s.char_at(last - 1) == '3' {
-                match s.char_at(last - 2) {
-                    'i' => ty = ast::SignedIntLit(ast::TyI32, ast::Plus),
-                    'u' => ty = ast::UnsignedIntLit(ast::TyU32),
-                    _ => { }
-                }
-            }
-        },
-        '4' => {
-            if s.len() > 3 && s.char_at(last - 1) == '6' {
-                match s.char_at(last - 2) {
-                    'i' => ty = ast::SignedIntLit(ast::TyI64, ast::Plus),
-                    'u' => ty = ast::UnsignedIntLit(ast::TyU64),
-                    _ => { }
+    if let Some(suf) = suffix {
+        if suf.is_empty() { sd.span_bug(sp, "found empty literal suffix in Some")}
+        ty = match suf {
+            "i"   => ast::SignedIntLit(ast::TyI, ast::Plus),
+            "i8"  => ast::SignedIntLit(ast::TyI8, ast::Plus),
+            "i16" => ast::SignedIntLit(ast::TyI16, ast::Plus),
+            "i32" => ast::SignedIntLit(ast::TyI32, ast::Plus),
+            "i64" => ast::SignedIntLit(ast::TyI64, ast::Plus),
+            "u"   => ast::UnsignedIntLit(ast::TyU),
+            "u8"  => ast::UnsignedIntLit(ast::TyU8),
+            "u16" => ast::UnsignedIntLit(ast::TyU16),
+            "u32" => ast::UnsignedIntLit(ast::TyU32),
+            "u64" => ast::UnsignedIntLit(ast::TyU64),
+            _ => {
+                // i<digits> and u<digits> look like widths, so lets
+                // give an error message along those lines
+                if looks_like_width_suffix(&['i', 'u'], suf) {
+                    sd.span_err(sp, &*format!("illegal width `{}` for integer literal; \
+                                              valid widths are 8, 16, 32 and 64",
+                                              suf.slice_from(1)));
+                } else {
+                    sd.span_err(sp, &*format!("illegal suffix `{}` for numeric literal", suf));
                 }
+
+                ty
             }
-        },
-        _ => { }
+        }
     }
 
-    debug!("The suffix is {}, base {}, the new string is {}, the original \
-           string was {}", ty, base, s, orig);
-
-    s = s.slice_to(s.len() - ty.suffix_len());
+    debug!("integer_lit: the type is {}, base {}, the new string is {}, the original \
+           string was {}, the original suffix was {}", ty, base, s, orig, suffix);
 
     let res: u64 = match ::std::num::from_str_radix(s, base) {
         Some(r) => r,
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 50b1a2204b0..a6fe3902395 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -646,6 +646,20 @@ impl<'a> Parser<'a> {
         }
     }
 
+    pub fn expect_no_suffix(&mut self, sp: Span, kind: &str, suffix: Option<ast::Name>) {
+        match suffix {
+            None => {/* everything ok */}
+            Some(suf) => {
+                let text = suf.as_str();
+                if text.is_empty() {
+                    self.span_bug(sp, "found empty literal suffix in Some")
+                }
+                self.span_err(sp, &*format!("{} with a suffix is illegal", kind));
+            }
+        }
+    }
+
+
     /// Attempt to consume a `<`. If `<<` is seen, replace it with a single
     /// `<` and continue. If a `<` is not seen, return false.
     ///
@@ -968,6 +982,9 @@ impl<'a> Parser<'a> {
     pub fn span_err(&mut self, sp: Span, m: &str) {
         self.sess.span_diagnostic.span_err(sp, m)
     }
+    pub fn span_bug(&mut self, sp: Span, m: &str) -> ! {
+        self.sess.span_diagnostic.span_bug(sp, m)
+    }
     pub fn abort_if_errors(&mut self) {
         self.sess.span_diagnostic.handler().abort_if_errors();
     }
@@ -1502,17 +1519,17 @@ impl<'a> Parser<'a> {
         } else if self.eat_keyword(keywords::Proc) {
             self.parse_proc_type(Vec::new())
         } else if self.token == token::Lt {
-            // QUALIFIED PATH
+            // QUALIFIED PATH `<TYPE as TRAIT_REF>::item`
             self.bump();
-            let for_type = self.parse_ty(true);
+            let self_type = self.parse_ty(true);
             self.expect_keyword(keywords::As);
-            let trait_name = self.parse_path(LifetimeAndTypesWithoutColons);
+            let trait_ref = self.parse_trait_ref();
             self.expect(&token::Gt);
             self.expect(&token::ModSep);
             let item_name = self.parse_ident();
             TyQPath(P(QPath {
-                for_type: for_type,
-                trait_name: trait_name.path,
+                self_type: self_type,
+                trait_ref: P(trait_ref),
                 item_name: item_name,
             }))
         } else if self.token == token::ModSep ||
@@ -1640,24 +1657,53 @@ impl<'a> Parser<'a> {
     /// Matches token_lit = LIT_INTEGER | ...
     pub fn lit_from_token(&mut self, tok: &token::Token) -> Lit_ {
         match *tok {
-            token::LitByte(i) => LitByte(parse::byte_lit(i.as_str()).val0()),
-            token::LitChar(i) => LitChar(parse::char_lit(i.as_str()).val0()),
-            token::LitInteger(s) => parse::integer_lit(s.as_str(),
-                                                        &self.sess.span_diagnostic,
-                                                       self.last_span),
-            token::LitFloat(s) => parse::float_lit(s.as_str()),
-            token::LitStr(s) => {
-                LitStr(token::intern_and_get_ident(parse::str_lit(s.as_str()).as_slice()),
-                       ast::CookedStr)
-            }
-            token::LitStrRaw(s, n) => {
-                LitStr(token::intern_and_get_ident(parse::raw_str_lit(s.as_str()).as_slice()),
-                       ast::RawStr(n))
+            token::Literal(lit, suf) => {
+                let (suffix_illegal, out) = match lit {
+                    token::Byte(i) => (true, LitByte(parse::byte_lit(i.as_str()).val0())),
+                    token::Char(i) => (true, LitChar(parse::char_lit(i.as_str()).val0())),
+
+                    // there are some valid suffixes for integer and
+                    // float literals, so all the handling is done
+                    // internally.
+                    token::Integer(s) => {
+                        (false, parse::integer_lit(s.as_str(),
+                                                   suf.as_ref().map(|s| s.as_str()),
+                                                   &self.sess.span_diagnostic,
+                                                   self.last_span))
+                    }
+                    token::Float(s) => {
+                        (false, parse::float_lit(s.as_str(),
+                                                 suf.as_ref().map(|s| s.as_str()),
+                                                  &self.sess.span_diagnostic,
+                                                 self.last_span))
+                    }
+
+                    token::Str_(s) => {
+                        (true,
+                         LitStr(token::intern_and_get_ident(parse::str_lit(s.as_str()).as_slice()),
+                                ast::CookedStr))
+                    }
+                    token::StrRaw(s, n) => {
+                        (true,
+                         LitStr(
+                            token::intern_and_get_ident(
+                                parse::raw_str_lit(s.as_str()).as_slice()),
+                            ast::RawStr(n)))
+                    }
+                    token::Binary(i) =>
+                        (true, LitBinary(parse::binary_lit(i.as_str()))),
+                    token::BinaryRaw(i, _) =>
+                        (true,
+                         LitBinary(Rc::new(i.as_str().as_bytes().iter().map(|&x| x).collect()))),
+                };
+
+                if suffix_illegal {
+                    let sp = self.last_span;
+                    self.expect_no_suffix(sp, &*format!("{} literal", lit.short_name()), suf)
+                }
+
+                out
             }
-            token::LitBinary(i) =>
-                LitBinary(parse::binary_lit(i.as_str())),
-            token::LitBinaryRaw(i, _) =>
-                LitBinary(Rc::new(i.as_str().as_bytes().iter().map(|&x| x).collect())),
             _ => { self.unexpected_last(tok); }
         }
     }
@@ -2424,7 +2470,10 @@ impl<'a> Parser<'a> {
                         }
                     }
                   }
-                  token::LitInteger(n) => {
+                  token::Literal(token::Integer(n), suf) => {
+                    let sp = self.span;
+                    self.expect_no_suffix(sp, "tuple index", suf);
+
                     let index = n.as_str();
                     let dot = self.last_span.hi;
                     hi = self.span.hi;
@@ -2449,7 +2498,7 @@ impl<'a> Parser<'a> {
                         }
                     }
                   }
-                  token::LitFloat(n) => {
+                  token::Literal(token::Float(n), _suf) => {
                     self.bump();
                     let last_span = self.last_span;
                     let fstr = n.as_str();
@@ -5085,12 +5134,17 @@ impl<'a> Parser<'a> {
                 self.expect(&token::Semi);
                 (path, the_ident)
             },
-            token::LitStr(..) | token::LitStrRaw(..) => {
-                let path = self.parse_str();
+            token::Literal(token::Str_(..), suf) | token::Literal(token::StrRaw(..), suf) => {
+                let sp = self.span;
+                self.expect_no_suffix(sp, "extern crate name", suf);
+                // forgo the internal suffix check of `parse_str` to
+                // avoid repeats (this unwrap will always succeed due
+                // to the restriction of the `match`)
+                let (s, style, _) = self.parse_optional_str().unwrap();
                 self.expect_keyword(keywords::As);
                 let the_ident = self.parse_ident();
                 self.expect(&token::Semi);
-                (Some(path), the_ident)
+                (Some((s, style)), the_ident)
             },
             _ => {
                 let span = self.span;
@@ -5267,7 +5321,9 @@ impl<'a> Parser<'a> {
     /// the `extern` keyword, if one is found.
     fn parse_opt_abi(&mut self) -> Option<abi::Abi> {
         match self.token {
-            token::LitStr(s) | token::LitStrRaw(s, _) => {
+            token::Literal(token::Str_(s), suf) | token::Literal(token::StrRaw(s, _), suf) => {
+                let sp = self.span;
+                self.expect_no_suffix(sp, "ABI spec", suf);
                 self.bump();
                 let the_string = s.as_str();
                 match abi::lookup(the_string) {
@@ -5910,21 +5966,27 @@ impl<'a> Parser<'a> {
     }
 
     pub fn parse_optional_str(&mut self)
-                              -> Option<(InternedString, ast::StrStyle)> {
-        let (s, style) = match self.token {
-            token::LitStr(s) => (self.id_to_interned_str(s.ident()), ast::CookedStr),
-            token::LitStrRaw(s, n) => {
-                (self.id_to_interned_str(s.ident()), ast::RawStr(n))
+                              -> Option<(InternedString, ast::StrStyle, Option<ast::Name>)> {
+        let ret = match self.token {
+            token::Literal(token::Str_(s), suf) => {
+                (self.id_to_interned_str(s.ident()), ast::CookedStr, suf)
+            }
+            token::Literal(token::StrRaw(s, n), suf) => {
+                (self.id_to_interned_str(s.ident()), ast::RawStr(n), suf)
             }
             _ => return None
         };
         self.bump();
-        Some((s, style))
+        Some(ret)
     }
 
     pub fn parse_str(&mut self) -> (InternedString, StrStyle) {
         match self.parse_optional_str() {
-            Some(s) => { s }
+            Some((s, style, suf)) => {
+                let sp = self.last_span;
+                self.expect_no_suffix(sp, "str literal", suf);
+                (s, style)
+            }
             _ =>  self.fatal("expected string literal")
         }
     }
diff --git a/src/libsyntax/parse/token.rs b/src/libsyntax/parse/token.rs
index 298328d73ef..4272b57a4dc 100644
--- a/src/libsyntax/parse/token.rs
+++ b/src/libsyntax/parse/token.rs
@@ -12,6 +12,7 @@ pub use self::BinOpToken::*;
 pub use self::Nonterminal::*;
 pub use self::DelimToken::*;
 pub use self::IdentStyle::*;
+pub use self::Lit::*;
 pub use self::Token::*;
 
 use ast;
@@ -59,6 +60,31 @@ pub enum IdentStyle {
     Plain,
 }
 
+#[deriving(Clone, Encodable, Decodable, PartialEq, Eq, Hash, Show)]
+pub enum Lit {
+    Byte(ast::Name),
+    Char(ast::Name),
+    Integer(ast::Name),
+    Float(ast::Name),
+    Str_(ast::Name),
+    StrRaw(ast::Name, uint), /* raw str delimited by n hash symbols */
+    Binary(ast::Name),
+    BinaryRaw(ast::Name, uint), /* raw binary str delimited by n hash symbols */
+}
+
+impl Lit {
+    pub fn short_name(&self) -> &'static str {
+        match *self {
+            Byte(_) => "byte",
+            Char(_) => "char",
+            Integer(_) => "integer",
+            Float(_) => "float",
+            Str_(_) | StrRaw(..) => "str",
+            Binary(_) | BinaryRaw(..) => "binary str"
+        }
+    }
+}
+
 #[allow(non_camel_case_types)]
 #[deriving(Clone, Encodable, Decodable, PartialEq, Eq, Hash, Show)]
 pub enum Token {
@@ -98,14 +124,7 @@ pub enum Token {
     CloseDelim(DelimToken),
 
     /* Literals */
-    LitByte(ast::Name),
-    LitChar(ast::Name),
-    LitInteger(ast::Name),
-    LitFloat(ast::Name),
-    LitStr(ast::Name),
-    LitStrRaw(ast::Name, uint), /* raw str delimited by n hash symbols */
-    LitBinary(ast::Name),
-    LitBinaryRaw(ast::Name, uint), /* raw binary str delimited by n hash symbols */
+    Literal(Lit, Option<ast::Name>),
 
     /* Name components */
     Ident(ast::Ident, IdentStyle),
@@ -145,14 +164,7 @@ impl Token {
             Ident(_, _)                 => true,
             Underscore                  => true,
             Tilde                       => true,
-            LitByte(_)                  => true,
-            LitChar(_)                  => true,
-            LitInteger(_)               => true,
-            LitFloat(_)                 => true,
-            LitStr(_)                   => true,
-            LitStrRaw(_, _)             => true,
-            LitBinary(_)                => true,
-            LitBinaryRaw(_, _)          => true,
+            Literal(_, _)               => true,
             Pound                       => true,
             At                          => true,
             Not                         => true,
@@ -173,15 +185,8 @@ impl Token {
     /// Returns `true` if the token is any literal
     pub fn is_lit(&self) -> bool {
         match *self {
-            LitByte(_)          => true,
-            LitChar(_)          => true,
-            LitInteger(_)       => true,
-            LitFloat(_)         => true,
-            LitStr(_)           => true,
-            LitStrRaw(_, _)     => true,
-            LitBinary(_)        => true,
-            LitBinaryRaw(_, _)  => true,
-            _                   => false,
+            Literal(_, _) => true,
+            _          => false,
         }
     }