diff --git a/src/librustc/hir/lowering.rs b/src/librustc/hir/lowering.rs
index 6fd0ccb49b6d7..6958801d865bf 100644
--- a/src/librustc/hir/lowering.rs
+++ b/src/librustc/hir/lowering.rs
@@ -72,7 +72,7 @@ use syntax::ptr::P;
 use syntax::source_map::{self, respan, CompilerDesugaringKind, Spanned};
 use syntax::std_inject;
 use syntax::symbol::{keywords, Symbol};
-use syntax::tokenstream::{Delimited, TokenStream, TokenTree};
+use syntax::tokenstream::{TokenStream, TokenTree};
 use syntax::parse::token::Token;
 use syntax::visit::{self, Visitor};
 use syntax_pos::{Span, MultiSpan};
@@ -1088,12 +1088,10 @@ impl<'a> LoweringContext<'a> {
     fn lower_token_tree(&mut self, tree: TokenTree) -> TokenStream {
         match tree {
             TokenTree::Token(span, token) => self.lower_token(token, span),
-            TokenTree::Delimited(span, delimited) => TokenTree::Delimited(
+            TokenTree::Delimited(span, delim, tts) => TokenTree::Delimited(
                 span,
-                Delimited {
-                    delim: delimited.delim,
-                    tts: self.lower_token_stream(delimited.tts.into()).into(),
-                },
+                delim,
+                self.lower_token_stream(tts.into()).into(),
             ).into(),
         }
     }
diff --git a/src/librustc/ich/impls_syntax.rs b/src/librustc/ich/impls_syntax.rs
index db643e4fd726b..3211937d3ddc7 100644
--- a/src/librustc/ich/impls_syntax.rs
+++ b/src/librustc/ich/impls_syntax.rs
@@ -265,10 +265,10 @@ for tokenstream::TokenTree {
                 span.hash_stable(hcx, hasher);
                 hash_token(token, hcx, hasher);
             }
-            tokenstream::TokenTree::Delimited(span, ref delimited) => {
+            tokenstream::TokenTree::Delimited(span, delim, ref tts) => {
                 span.hash_stable(hcx, hasher);
-                std_hash::Hash::hash(&delimited.delim, hasher);
-                for sub_tt in delimited.stream().trees() {
+                std_hash::Hash::hash(&delim, hasher);
+                for sub_tt in tts.stream().trees() {
                     sub_tt.hash_stable(hcx, hasher);
                 }
             }
diff --git a/src/librustc_lint/builtin.rs b/src/librustc_lint/builtin.rs
index e0e790e9f2302..7dd5d3c1cbc4c 100644
--- a/src/librustc_lint/builtin.rs
+++ b/src/librustc_lint/builtin.rs
@@ -1540,8 +1540,8 @@ impl KeywordIdents {
                     }
                     _ => {},
                 }
-                TokenTree::Delimited(_, ref delim) => {
-                    self.check_tokens(cx, delim.tts.clone().into())
+                TokenTree::Delimited(_, _, tts) => {
+                    self.check_tokens(cx, tts.stream())
                 },
             }
         }
diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index f25f456e3ae40..0792b2dc49c27 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -1235,7 +1235,7 @@ pub enum MacDelimiter {
 
 impl Mac_ {
     pub fn stream(&self) -> TokenStream {
-        self.tts.clone().into()
+        self.tts.stream()
     }
 }
 
diff --git a/src/libsyntax/attr/mod.rs b/src/libsyntax/attr/mod.rs
index 7e8384bec6807..7723c15a266f1 100644
--- a/src/libsyntax/attr/mod.rs
+++ b/src/libsyntax/attr/mod.rs
@@ -34,7 +34,7 @@ use parse::token::{self, Token};
 use ptr::P;
 use symbol::Symbol;
 use ThinVec;
-use tokenstream::{TokenStream, TokenTree, Delimited, DelimSpan};
+use tokenstream::{TokenStream, TokenTree, DelimSpan};
 use GLOBALS;
 
 use std::iter;
@@ -549,10 +549,11 @@ impl MetaItemKind {
                     }
                     tokens.push(item.node.tokens());
                 }
-                TokenTree::Delimited(DelimSpan::from_single(span), Delimited {
-                    delim: token::Paren,
-                    tts: TokenStream::concat(tokens).into(),
-                }).into()
+                TokenTree::Delimited(
+                    DelimSpan::from_single(span),
+                    token::Paren,
+                    TokenStream::concat(tokens).into(),
+                ).into()
             }
         }
     }
@@ -570,9 +571,9 @@ impl MetaItemKind {
                     None
                 };
             }
-            Some(TokenTree::Delimited(_, ref delimited)) if delimited.delim == token::Paren => {
+            Some(TokenTree::Delimited(_, delim, ref tts)) if delim == token::Paren => {
                 tokens.next();
-                delimited.stream()
+                tts.stream()
             }
             _ => return Some(MetaItemKind::Word),
         };
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index 06e7b4657849f..f4e9a7e409359 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -622,9 +622,9 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
     fn extract_proc_macro_attr_input(&self, tokens: TokenStream, span: Span) -> TokenStream {
         let mut trees = tokens.trees();
         match trees.next() {
-            Some(TokenTree::Delimited(_, delim)) => {
+            Some(TokenTree::Delimited(_, _, tts)) => {
                 if trees.next().is_none() {
-                    return delim.tts.into()
+                    return tts.into()
                 }
             }
             Some(TokenTree::Token(..)) => {}
diff --git a/src/libsyntax/ext/quote.rs b/src/libsyntax/ext/quote.rs
index 91818992fe1f1..c3497a17806b1 100644
--- a/src/libsyntax/ext/quote.rs
+++ b/src/libsyntax/ext/quote.rs
@@ -36,7 +36,7 @@ pub mod rt {
     use symbol::Symbol;
     use ThinVec;
 
-    use tokenstream::{self, DelimSpan, TokenTree, TokenStream};
+    use tokenstream::{DelimSpan, TokenTree, TokenStream};
 
     pub use parse::new_parser_from_tts;
     pub use syntax_pos::{BytePos, Span, DUMMY_SP, FileName};
@@ -246,9 +246,9 @@ pub mod rt {
             inner.push(self.tokens.clone());
 
             let delim_span = DelimSpan::from_single(self.span);
-            r.push(TokenTree::Delimited(delim_span, tokenstream::Delimited {
-                delim: token::Bracket, tts: TokenStream::concat(inner).into()
-            }));
+            r.push(TokenTree::Delimited(
+                delim_span, token::Bracket, TokenStream::concat(inner).into()
+            ));
             r
         }
     }
@@ -262,10 +262,9 @@ pub mod rt {
 
     impl ToTokens for () {
         fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree> {
-            vec![TokenTree::Delimited(DelimSpan::dummy(), tokenstream::Delimited {
-                delim: token::Paren,
-                tts: TokenStream::empty().into(),
-            })]
+            vec![
+                TokenTree::Delimited(DelimSpan::dummy(), token::Paren, TokenStream::empty().into())
+            ]
         }
     }
 
@@ -382,8 +381,6 @@ pub mod rt {
 
 // Replaces `Token::OpenDelim .. Token::CloseDelim` with `TokenTree::Delimited(..)`.
 pub fn unflatten(tts: Vec<TokenTree>) -> Vec<TokenTree> {
-    use tokenstream::Delimited;
-
     let mut results = Vec::new();
     let mut result = Vec::new();
     let mut open_span = DUMMY_SP;
@@ -395,10 +392,11 @@ pub fn unflatten(tts: Vec<TokenTree>) -> Vec<TokenTree> {
             }
             TokenTree::Token(span, token::CloseDelim(delim)) => {
                 let delim_span = DelimSpan::from_pair(open_span, span);
-                let tree = TokenTree::Delimited(delim_span, Delimited {
+                let tree = TokenTree::Delimited(
+                    delim_span,
                     delim,
-                    tts: result.into_iter().map(TokenStream::from).collect::<TokenStream>().into(),
-                });
+                    result.into_iter().map(TokenStream::from).collect::<TokenStream>().into(),
+                );
                 result = results.pop().unwrap();
                 result.push(tree);
             }
@@ -758,10 +756,10 @@ fn statements_mk_tt(cx: &ExtCtxt, tt: &TokenTree, quoted: bool) -> Vec<ast::Stmt
                                     vec![e_tok]);
             vec![cx.stmt_expr(e_push)]
         },
-        TokenTree::Delimited(span, ref delimed) => {
-            let mut stmts = statements_mk_tt(cx, &delimed.open_tt(span.open), false);
-            stmts.extend(statements_mk_tts(cx, delimed.stream()));
-            stmts.extend(statements_mk_tt(cx, &delimed.close_tt(span.close), false));
+        TokenTree::Delimited(span, delim, ref tts) => {
+            let mut stmts = statements_mk_tt(cx, &TokenTree::open_tt(span.open, delim), false);
+            stmts.extend(statements_mk_tts(cx, tts.stream()));
+            stmts.extend(statements_mk_tt(cx, &TokenTree::close_tt(span.close, delim), false));
             stmts
         }
     }
diff --git a/src/libsyntax/ext/tt/quoted.rs b/src/libsyntax/ext/tt/quoted.rs
index 1dab029785481..b142f09cdbc74 100644
--- a/src/libsyntax/ext/tt/quoted.rs
+++ b/src/libsyntax/ext/tt/quoted.rs
@@ -280,17 +280,17 @@ where
         // `tree` is a `$` token. Look at the next token in `trees`
         tokenstream::TokenTree::Token(span, token::Dollar) => match trees.next() {
             // `tree` is followed by a delimited set of token trees. This indicates the beginning
-            // of a repetition sequence in the macro (e.g., `$(pat)*`).
-            Some(tokenstream::TokenTree::Delimited(span, delimited)) => {
+            // of a repetition sequence in the macro (e.g. `$(pat)*`).
+            Some(tokenstream::TokenTree::Delimited(span, delim, tts)) => {
                 // Must have `(` not `{` or `[`
-                if delimited.delim != token::Paren {
-                    let tok = pprust::token_to_string(&token::OpenDelim(delimited.delim));
+                if delim != token::Paren {
+                    let tok = pprust::token_to_string(&token::OpenDelim(delim));
                     let msg = format!("expected `(`, found `{}`", tok);
                     sess.span_diagnostic.span_err(span.entire(), &msg);
                 }
                 // Parse the contents of the sequence itself
                 let sequence = parse(
-                    delimited.tts.into(),
+                    tts.into(),
                     expect_matchers,
                     sess,
                     features,
@@ -354,12 +354,12 @@ where
 
         // `tree` is the beginning of a delimited set of tokens (e.g., `(` or `{`). We need to
         // descend into the delimited set and further parse it.
-        tokenstream::TokenTree::Delimited(span, delimited) => TokenTree::Delimited(
+        tokenstream::TokenTree::Delimited(span, delim, tts) => TokenTree::Delimited(
             span,
             Lrc::new(Delimited {
-                delim: delimited.delim,
+                delim: delim,
                 tts: parse(
-                    delimited.tts.into(),
+                    tts.into(),
                     expect_matchers,
                     sess,
                     features,
diff --git a/src/libsyntax/ext/tt/transcribe.rs b/src/libsyntax/ext/tt/transcribe.rs
index 3d897d17e0b5c..a76779ffebdc0 100644
--- a/src/libsyntax/ext/tt/transcribe.rs
+++ b/src/libsyntax/ext/tt/transcribe.rs
@@ -17,7 +17,7 @@ use fold::noop_fold_tt;
 use parse::token::{self, Token, NtTT};
 use smallvec::SmallVec;
 use syntax_pos::DUMMY_SP;
-use tokenstream::{TokenStream, TokenTree, Delimited, DelimSpan};
+use tokenstream::{TokenStream, TokenTree, DelimSpan};
 
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::Lrc;
@@ -105,10 +105,11 @@ pub fn transcribe(cx: &ExtCtxt,
                     if result_stack.is_empty() {
                         return TokenStream::concat(result);
                     }
-                    let tree = TokenTree::Delimited(span, Delimited {
-                        delim: forest.delim,
-                        tts: TokenStream::concat(result).into(),
-                    });
+                    let tree = TokenTree::Delimited(
+                        span,
+                        forest.delim,
+                        TokenStream::concat(result).into(),
+                    );
                     result = result_stack.pop().unwrap();
                     result.push(tree.into());
                 }
diff --git a/src/libsyntax/fold.rs b/src/libsyntax/fold.rs
index 82f52931cad7c..ecb0245263853 100644
--- a/src/libsyntax/fold.rs
+++ b/src/libsyntax/fold.rs
@@ -605,12 +605,10 @@ pub fn noop_fold_tt<T: Folder>(tt: TokenTree, fld: &mut T) -> TokenTree {
     match tt {
         TokenTree::Token(span, tok) =>
             TokenTree::Token(fld.new_span(span), fld.fold_token(tok)),
-        TokenTree::Delimited(span, delimed) => TokenTree::Delimited(
+        TokenTree::Delimited(span, delim, tts) => TokenTree::Delimited(
             DelimSpan::from_pair(fld.new_span(span.open), fld.new_span(span.close)),
-            Delimited {
-                tts: fld.fold_tts(delimed.stream()).into(),
-                delim: delimed.delim,
-            }
+            delim,
+            fld.fold_tts(tts.stream()).into(),
         ),
     }
 }
diff --git a/src/libsyntax/parse/lexer/tokentrees.rs b/src/libsyntax/parse/lexer/tokentrees.rs
index 8047ab0146514..86c87cf898d09 100644
--- a/src/libsyntax/parse/lexer/tokentrees.rs
+++ b/src/libsyntax/parse/lexer/tokentrees.rs
@@ -11,7 +11,7 @@
 use print::pprust::token_to_string;
 use parse::lexer::StringReader;
 use parse::{token, PResult};
-use tokenstream::{Delimited, DelimSpan, TokenStream, TokenTree};
+use tokenstream::{DelimSpan, TokenStream, TokenTree};
 
 impl<'a> StringReader<'a> {
     // Parse a stream of tokens into a list of `TokenTree`s, up to an `Eof`.
@@ -155,10 +155,11 @@ impl<'a> StringReader<'a> {
                     _ => {}
                 }
 
-                Ok(TokenTree::Delimited(delim_span, Delimited {
+                Ok(TokenTree::Delimited(
+                    delim_span,
                     delim,
-                    tts: tts.into(),
-                }).into())
+                    tts.into(),
+                ).into())
             },
             token::CloseDelim(_) => {
                 // An unexpected closing delimiter (i.e., there is no
diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index 866dba24dcb0a..eb71003d3d0cf 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -764,7 +764,7 @@ mod tests {
     use attr::first_attr_value_str_by_name;
     use parse;
     use print::pprust::item_to_string;
-    use tokenstream::{self, DelimSpan, TokenTree};
+    use tokenstream::{DelimSpan, TokenTree};
     use util::parser_testing::string_to_stream;
     use util::parser_testing::{string_to_expr, string_to_item};
     use with_globals;
@@ -795,42 +795,41 @@ mod tests {
                     Some(&TokenTree::Token(_, token::Ident(name_macro_rules, false))),
                     Some(&TokenTree::Token(_, token::Not)),
                     Some(&TokenTree::Token(_, token::Ident(name_zip, false))),
-                    Some(&TokenTree::Delimited(_, ref macro_delimed)),
+                    Some(&TokenTree::Delimited(_, macro_delim, ref macro_tts)),
                 )
                 if name_macro_rules.name == "macro_rules"
                 && name_zip.name == "zip" => {
-                    let tts = &macro_delimed.stream().trees().collect::<Vec<_>>();
+                    let tts = &macro_tts.stream().trees().collect::<Vec<_>>();
                     match (tts.len(), tts.get(0), tts.get(1), tts.get(2)) {
                         (
                             3,
-                            Some(&TokenTree::Delimited(_, ref first_delimed)),
+                            Some(&TokenTree::Delimited(_, first_delim, ref first_tts)),
                             Some(&TokenTree::Token(_, token::FatArrow)),
-                            Some(&TokenTree::Delimited(_, ref second_delimed)),
+                            Some(&TokenTree::Delimited(_, second_delim, ref second_tts)),
                         )
-                        if macro_delimed.delim == token::Paren => {
-                            let tts = &first_delimed.stream().trees().collect::<Vec<_>>();
+                        if macro_delim == token::Paren => {
+                            let tts = &first_tts.stream().trees().collect::<Vec<_>>();
                             match (tts.len(), tts.get(0), tts.get(1)) {
                                 (
                                     2,
                                     Some(&TokenTree::Token(_, token::Dollar)),
                                     Some(&TokenTree::Token(_, token::Ident(ident, false))),
                                 )
-                                if first_delimed.delim == token::Paren && ident.name == "a" => {},
-                                _ => panic!("value 3: {:?}", *first_delimed),
+                                if first_delim == token::Paren && ident.name == "a" => {},
+                                _ => panic!("value 3: {:?} {:?}", first_delim, first_tts),
                             }
-                            let tts = &second_delimed.stream().trees().collect::<Vec<_>>();
+                            let tts = &second_tts.stream().trees().collect::<Vec<_>>();
                             match (tts.len(), tts.get(0), tts.get(1)) {
                                 (
                                     2,
                                     Some(&TokenTree::Token(_, token::Dollar)),
                                     Some(&TokenTree::Token(_, token::Ident(ident, false))),
                                 )
-                                if second_delimed.delim == token::Paren
-                                && ident.name == "a" => {},
-                                _ => panic!("value 4: {:?}", *second_delimed),
+                                if second_delim == token::Paren && ident.name == "a" => {},
+                                _ => panic!("value 4: {:?} {:?}", second_delim, second_tts),
                             }
                         },
-                        _ => panic!("value 2: {:?}", *macro_delimed),
+                        _ => panic!("value 2: {:?} {:?}", macro_delim, macro_tts),
                     }
                 },
                 _ => panic!("value: {:?}",tts),
@@ -848,26 +847,24 @@ mod tests {
                 TokenTree::Token(sp(3, 4), token::Ident(Ident::from_str("a"), false)).into(),
                 TokenTree::Delimited(
                     DelimSpan::from_pair(sp(5, 6), sp(13, 14)),
-                    tokenstream::Delimited {
-                        delim: token::DelimToken::Paren,
-                        tts: TokenStream::concat(vec![
-                            TokenTree::Token(sp(6, 7),
-                                             token::Ident(Ident::from_str("b"), false)).into(),
-                            TokenTree::Token(sp(8, 9), token::Colon).into(),
-                            TokenTree::Token(sp(10, 13),
-                                             token::Ident(Ident::from_str("i32"), false)).into(),
-                        ]).into(),
-                    }).into(),
+                    token::DelimToken::Paren,
+                    TokenStream::concat(vec![
+                        TokenTree::Token(sp(6, 7),
+                                         token::Ident(Ident::from_str("b"), false)).into(),
+                        TokenTree::Token(sp(8, 9), token::Colon).into(),
+                        TokenTree::Token(sp(10, 13),
+                                         token::Ident(Ident::from_str("i32"), false)).into(),
+                    ]).into(),
+                ).into(),
                 TokenTree::Delimited(
                     DelimSpan::from_pair(sp(15, 16), sp(20, 21)),
-                    tokenstream::Delimited {
-                        delim: token::DelimToken::Brace,
-                        tts: TokenStream::concat(vec![
-                            TokenTree::Token(sp(17, 18),
-                                             token::Ident(Ident::from_str("b"), false)).into(),
-                            TokenTree::Token(sp(18, 19), token::Semi).into(),
-                        ]).into(),
-                    }).into()
+                    token::DelimToken::Brace,
+                    TokenStream::concat(vec![
+                        TokenTree::Token(sp(17, 18),
+                                         token::Ident(Ident::from_str("b"), false)).into(),
+                        TokenTree::Token(sp(18, 19), token::Semi).into(),
+                    ]).into(),
+                ).into()
             ]);
 
             assert_eq!(tts, expected);
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index e3a3454de497f..ded6da9f3adb8 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -48,13 +48,14 @@ use errors::{self, Applicability, DiagnosticBuilder, DiagnosticId};
 use parse::{self, SeqSep, classify, token};
 use parse::lexer::TokenAndSpan;
 use parse::lexer::comments::{doc_comment_style, strip_doc_comment_decoration};
+use parse::token::DelimToken;
 use parse::{new_sub_parser_from_file, ParseSess, Directory, DirectoryOwnership};
 use util::parser::{AssocOp, Fixity};
 use print::pprust;
 use ptr::P;
 use parse::PResult;
 use ThinVec;
-use tokenstream::{self, Delimited, DelimSpan, ThinTokenStream, TokenTree, TokenStream};
+use tokenstream::{self, DelimSpan, ThinTokenStream, TokenTree, TokenStream};
 use symbol::{Symbol, keywords};
 
 use std::borrow::Cow;
@@ -293,13 +294,13 @@ enum LastToken {
 }
 
 impl TokenCursorFrame {
-    fn new(sp: DelimSpan, delimited: &Delimited) -> Self {
+    fn new(sp: DelimSpan, delim: DelimToken, tts: &ThinTokenStream) -> Self {
         TokenCursorFrame {
-            delim: delimited.delim,
+            delim: delim,
             span: sp,
-            open_delim: delimited.delim == token::NoDelim,
-            tree_cursor: delimited.stream().into_trees(),
-            close_delim: delimited.delim == token::NoDelim,
+            open_delim: delim == token::NoDelim,
+            tree_cursor: tts.stream().into_trees(),
+            close_delim: delim == token::NoDelim,
             last_token: LastToken::Was(None),
         }
     }
@@ -310,14 +311,12 @@ impl TokenCursor {
         loop {
             let tree = if !self.frame.open_delim {
                 self.frame.open_delim = true;
-                Delimited { delim: self.frame.delim, tts: TokenStream::empty().into() }
-                    .open_tt(self.frame.span.open)
+                TokenTree::open_tt(self.frame.span.open, self.frame.delim)
             } else if let Some(tree) = self.frame.tree_cursor.next() {
                 tree
             } else if !self.frame.close_delim {
                 self.frame.close_delim = true;
-                Delimited { delim: self.frame.delim, tts: TokenStream::empty().into() }
-                    .close_tt(self.frame.span.close)
+                TokenTree::close_tt(self.frame.span.close, self.frame.delim)
             } else if let Some(frame) = self.stack.pop() {
                 self.frame = frame;
                 continue
@@ -332,8 +331,8 @@ impl TokenCursor {
 
             match tree {
                 TokenTree::Token(sp, tok) => return TokenAndSpan { tok: tok, sp: sp },
-                TokenTree::Delimited(sp, ref delimited) => {
-                    let frame = TokenCursorFrame::new(sp, delimited);
+                TokenTree::Delimited(sp, delim, tts) => {
+                    let frame = TokenCursorFrame::new(sp, delim, &tts);
                     self.stack.push(mem::replace(&mut self.frame, frame));
                 }
             }
@@ -362,25 +361,28 @@ impl TokenCursor {
         }
 
         let delim_span = DelimSpan::from_single(sp);
-        let body = TokenTree::Delimited(delim_span, Delimited {
-            delim: token::Bracket,
-            tts: [TokenTree::Token(sp, token::Ident(ast::Ident::from_str("doc"), false)),
-                  TokenTree::Token(sp, token::Eq),
-                  TokenTree::Token(sp, token::Literal(
-                      token::StrRaw(Symbol::intern(&stripped), num_of_hashes), None))]
-                .iter().cloned().collect::<TokenStream>().into(),
-        });
+        let body = TokenTree::Delimited(
+            delim_span,
+            token::Bracket,
+            [TokenTree::Token(sp, token::Ident(ast::Ident::from_str("doc"), false)),
+             TokenTree::Token(sp, token::Eq),
+             TokenTree::Token(sp, token::Literal(
+                token::StrRaw(Symbol::intern(&stripped), num_of_hashes), None))
+            ]
+            .iter().cloned().collect::<TokenStream>().into(),
+        );
 
-        self.stack.push(mem::replace(&mut self.frame, TokenCursorFrame::new(delim_span, &Delimited {
-            delim: token::NoDelim,
-            tts: if doc_comment_style(&name.as_str()) == AttrStyle::Inner {
+        self.stack.push(mem::replace(&mut self.frame, TokenCursorFrame::new(
+            delim_span,
+            token::NoDelim,
+            &if doc_comment_style(&name.as_str()) == AttrStyle::Inner {
                 [TokenTree::Token(sp, token::Pound), TokenTree::Token(sp, token::Not), body]
                     .iter().cloned().collect::<TokenStream>().into()
             } else {
                 [TokenTree::Token(sp, token::Pound), body]
                     .iter().cloned().collect::<TokenStream>().into()
             },
-        })));
+        )));
 
         self.next()
     }
@@ -561,10 +563,11 @@ impl<'a> Parser<'a> {
             root_module_name: None,
             expected_tokens: Vec::new(),
             token_cursor: TokenCursor {
-                frame: TokenCursorFrame::new(DelimSpan::dummy(), &Delimited {
-                    delim: token::NoDelim,
-                    tts: tokens.into(),
-                }),
+                frame: TokenCursorFrame::new(
+                    DelimSpan::dummy(),
+                    token::NoDelim,
+                    &tokens.into(),
+                ),
                 stack: Vec::new(),
             },
             desugar_doc_comments,
@@ -1238,7 +1241,7 @@ impl<'a> Parser<'a> {
         f(&match self.token_cursor.frame.tree_cursor.look_ahead(dist - 1) {
             Some(tree) => match tree {
                 TokenTree::Token(_, tok) => tok,
-                TokenTree::Delimited(_, delimited) => token::OpenDelim(delimited.delim),
+                TokenTree::Delimited(_, delim, _) => token::OpenDelim(delim),
             },
             None => token::CloseDelim(self.token_cursor.frame.delim),
         })
@@ -1251,7 +1254,7 @@ impl<'a> Parser<'a> {
 
         match self.token_cursor.frame.tree_cursor.look_ahead(dist - 1) {
             Some(TokenTree::Token(span, _)) => span,
-            Some(TokenTree::Delimited(span, _)) => span.entire(),
+            Some(TokenTree::Delimited(span, ..)) => span.entire(),
             None => self.look_ahead_span(dist - 1),
         }
     }
@@ -2317,8 +2320,8 @@ impl<'a> Parser<'a> {
                 return Err(err)
             }
         };
-        let delimited = match self.parse_token_tree() {
-            TokenTree::Delimited(_, delimited) => delimited,
+        let tts = match self.parse_token_tree() {
+            TokenTree::Delimited(_, _, tts) => tts,
             _ => unreachable!(),
         };
         let delim = match delim {
@@ -2327,7 +2330,7 @@ impl<'a> Parser<'a> {
             token::Brace => MacDelimiter::Brace,
             token::NoDelim => self.bug("unexpected no delimiter"),
         };
-        Ok((delim, delimited.stream().into()))
+        Ok((delim, tts.stream().into()))
     }
 
     /// At the bottom (top?) of the precedence hierarchy,
@@ -2892,10 +2895,11 @@ impl<'a> Parser<'a> {
                                          self.token_cursor.stack.pop().unwrap());
                 self.span = frame.span.entire();
                 self.bump();
-                TokenTree::Delimited(frame.span, Delimited {
-                    delim: frame.delim,
-                    tts: frame.tree_cursor.original_stream().into(),
-                })
+                TokenTree::Delimited(
+                    frame.span,
+                    frame.delim,
+                    frame.tree_cursor.original_stream().into(),
+                )
             },
             token::CloseDelim(_) | token::Eof => unreachable!(),
             _ => {
@@ -4609,7 +4613,7 @@ impl<'a> Parser<'a> {
                 let ident = self.parse_ident()?;
                 let tokens = if self.check(&token::OpenDelim(token::Brace)) {
                     match self.parse_token_tree() {
-                        TokenTree::Delimited(_, ref delimited) => delimited.stream(),
+                        TokenTree::Delimited(_, _, tts) => tts.stream(),
                         _ => unreachable!(),
                     }
                 } else if self.check(&token::OpenDelim(token::Paren)) {
diff --git a/src/libsyntax/parse/token.rs b/src/libsyntax/parse/token.rs
index 6b9cc2f9792e3..8e4d3c0166bb2 100644
--- a/src/libsyntax/parse/token.rs
+++ b/src/libsyntax/parse/token.rs
@@ -818,16 +818,13 @@ fn prepend_attrs(sess: &ParseSess,
 
         brackets.push(attr.tokens.clone());
 
-        let tokens = tokenstream::Delimited {
-            delim: DelimToken::Bracket,
-            tts: brackets.build().into(),
-        };
         // The span we list here for `#` and for `[ ... ]` are both wrong in
         // that it encompasses more than each token, but it hopefully is "good
         // enough" for now at least.
         builder.push(tokenstream::TokenTree::Token(attr.span, Pound));
         let delim_span = DelimSpan::from_single(attr.span);
-        builder.push(tokenstream::TokenTree::Delimited(delim_span, tokens));
+        builder.push(tokenstream::TokenTree::Delimited(
+            delim_span, DelimToken::Bracket, brackets.build().into()));
     }
     builder.push(tokens.clone());
     Some(builder.build())
diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index e50f28897dd12..41165c7e36d58 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -815,12 +815,12 @@ pub trait PrintState<'a> {
                     _ => Ok(())
                 }
             }
-            TokenTree::Delimited(_, ref delimed) => {
-                self.writer().word(token_to_string(&delimed.open_token()))?;
+            TokenTree::Delimited(_, delim, tts) => {
+                self.writer().word(token_to_string(&token::OpenDelim(delim)))?;
                 self.writer().space()?;
-                self.print_tts(delimed.stream())?;
+                self.print_tts(tts.stream())?;
                 self.writer().space()?;
-                self.writer().word(token_to_string(&delimed.close_token()))
+                self.writer().word(token_to_string(&token::CloseDelim(delim)))
             },
         }
     }
diff --git a/src/libsyntax/tokenstream.rs b/src/libsyntax/tokenstream.rs
index 242299f1b1f6f..90191c54126d1 100644
--- a/src/libsyntax/tokenstream.rs
+++ b/src/libsyntax/tokenstream.rs
@@ -34,52 +34,6 @@ use util::RcVec;
 use std::borrow::Cow;
 use std::{fmt, iter, mem};
 
-/// A delimited sequence of token trees
-#[derive(Clone, PartialEq, RustcEncodable, RustcDecodable, Debug)]
-pub struct Delimited {
-    /// The type of delimiter
-    pub delim: DelimToken,
-    /// The delimited sequence of token trees
-    pub tts: ThinTokenStream,
-}
-
-impl Delimited {
-    /// Returns the opening delimiter as a token.
-    pub fn open_token(&self) -> token::Token {
-        token::OpenDelim(self.delim)
-    }
-
-    /// Returns the closing delimiter as a token.
-    pub fn close_token(&self) -> token::Token {
-        token::CloseDelim(self.delim)
-    }
-
-    /// Returns the opening delimiter as a token tree.
-    pub fn open_tt(&self, span: Span) -> TokenTree {
-        let open_span = if span.is_dummy() {
-            span
-        } else {
-            span.with_hi(span.lo() + BytePos(self.delim.len() as u32))
-        };
-        TokenTree::Token(open_span, self.open_token())
-    }
-
-    /// Returns the closing delimiter as a token tree.
-    pub fn close_tt(&self, span: Span) -> TokenTree {
-        let close_span = if span.is_dummy() {
-            span
-        } else {
-            span.with_lo(span.hi() - BytePos(self.delim.len() as u32))
-        };
-        TokenTree::Token(close_span, self.close_token())
-    }
-
-    /// Returns the token trees inside the delimiters.
-    pub fn stream(&self) -> TokenStream {
-        self.tts.clone().into()
-    }
-}
-
 /// When the main rust parser encounters a syntax-extension invocation, it
 /// parses the arguments to the invocation as a token-tree. This is a very
 /// loose structure, such that all sorts of different AST-fragments can
@@ -97,7 +51,7 @@ pub enum TokenTree {
     /// A single token
     Token(Span, token::Token),
     /// A delimited sequence of token trees
-    Delimited(DelimSpan, Delimited),
+    Delimited(DelimSpan, DelimToken, ThinTokenStream),
 }
 
 impl TokenTree {
@@ -116,9 +70,10 @@ impl TokenTree {
     pub fn eq_unspanned(&self, other: &TokenTree) -> bool {
         match (self, other) {
             (&TokenTree::Token(_, ref tk), &TokenTree::Token(_, ref tk2)) => tk == tk2,
-            (&TokenTree::Delimited(_, ref dl), &TokenTree::Delimited(_, ref dl2)) => {
-                dl.delim == dl2.delim &&
-                dl.stream().eq_unspanned(&dl2.stream())
+            (&TokenTree::Delimited(_, delim, ref tts),
+             &TokenTree::Delimited(_, delim2, ref tts2)) => {
+                delim == delim2 &&
+                tts.stream().eq_unspanned(&tts2.stream())
             }
             (_, _) => false,
         }
@@ -134,9 +89,10 @@ impl TokenTree {
             (&TokenTree::Token(_, ref tk), &TokenTree::Token(_, ref tk2)) => {
                 tk.probably_equal_for_proc_macro(tk2)
             }
-            (&TokenTree::Delimited(_, ref dl), &TokenTree::Delimited(_, ref dl2)) => {
-                dl.delim == dl2.delim &&
-                dl.stream().probably_equal_for_proc_macro(&dl2.stream())
+            (&TokenTree::Delimited(_, delim, ref tts),
+             &TokenTree::Delimited(_, delim2, ref tts2)) => {
+                delim == delim2 &&
+                tts.stream().probably_equal_for_proc_macro(&tts2.stream())
             }
             (_, _) => false,
         }
@@ -146,7 +102,7 @@ impl TokenTree {
     pub fn span(&self) -> Span {
         match *self {
             TokenTree::Token(sp, _) => sp,
-            TokenTree::Delimited(sp, _) => sp.entire(),
+            TokenTree::Delimited(sp, ..) => sp.entire(),
         }
     }
 
@@ -154,7 +110,7 @@ impl TokenTree {
     pub fn set_span(&mut self, span: Span) {
         match *self {
             TokenTree::Token(ref mut sp, _) => *sp = span,
-            TokenTree::Delimited(ref mut sp, _) => *sp = DelimSpan::from_single(span),
+            TokenTree::Delimited(ref mut sp, ..) => *sp = DelimSpan::from_single(span),
         }
     }
 
@@ -169,6 +125,26 @@ impl TokenTree {
     pub fn joint(self) -> TokenStream {
         TokenStream { kind: TokenStreamKind::JointTree(self) }
     }
+
+    /// Returns the opening delimiter as a token tree.
+    pub fn open_tt(span: Span, delim: DelimToken) -> TokenTree {
+        let open_span = if span.is_dummy() {
+            span
+        } else {
+            span.with_hi(span.lo() + BytePos(delim.len() as u32))
+        };
+        TokenTree::Token(open_span, token::OpenDelim(delim))
+    }
+
+    /// Returns the closing delimiter as a token tree.
+    pub fn close_tt(span: Span, delim: DelimToken) -> TokenTree {
+        let close_span = if span.is_dummy() {
+            span
+        } else {
+            span.with_lo(span.hi() - BytePos(delim.len() as u32))
+        };
+        TokenTree::Token(close_span, token::CloseDelim(delim))
+    }
 }
 
 /// # Token Streams
@@ -182,6 +158,10 @@ pub struct TokenStream {
     kind: TokenStreamKind,
 }
 
+// `TokenStream` is used a lot. Make sure it doesn't unintentionally get bigger.
+#[cfg(target_arch = "x86_64")]
+static_assert!(MEM_SIZE_OF_TOKEN_STREAM: mem::size_of::<TokenStream>() == 40);
+
 impl TokenStream {
     /// Given a `TokenStream` with a `Stream` of only two arguments, return a new `TokenStream`
     /// separating the two arguments with a comma for diagnostic suggestions.
@@ -198,7 +178,7 @@ impl TokenStream {
                             continue;
                         }
                         (TokenStreamKind::Tree(TokenTree::Token(sp, _)), _) => *sp,
-                        (TokenStreamKind::Tree(TokenTree::Delimited(sp, _)), _) => sp.entire(),
+                        (TokenStreamKind::Tree(TokenTree::Delimited(sp, ..)), _) => sp.entire(),
                         _ => continue,
                     };
                     let sp = sp.shrink_to_hi();
@@ -678,6 +658,12 @@ impl Cursor {
 #[derive(Debug, Clone)]
 pub struct ThinTokenStream(Option<RcVec<TokenStream>>);
 
+impl ThinTokenStream {
+    pub fn stream(&self) -> TokenStream {
+        self.clone().into()
+    }
+}
+
 impl From<TokenStream> for ThinTokenStream {
     fn from(stream: TokenStream) -> ThinTokenStream {
         ThinTokenStream(match stream.kind {
diff --git a/src/libsyntax/visit.rs b/src/libsyntax/visit.rs
index 4be831a0b3f6b..6747598f3753f 100644
--- a/src/libsyntax/visit.rs
+++ b/src/libsyntax/visit.rs
@@ -841,7 +841,7 @@ pub fn walk_attribute<'a, V: Visitor<'a>>(visitor: &mut V, attr: &'a Attribute)
 pub fn walk_tt<'a, V: Visitor<'a>>(visitor: &mut V, tt: TokenTree) {
     match tt {
         TokenTree::Token(_, tok) => visitor.visit_token(tok),
-        TokenTree::Delimited(_, delimed) => visitor.visit_tts(delimed.stream()),
+        TokenTree::Delimited(_, _, tts) => visitor.visit_tts(tts.stream()),
     }
 }
 
diff --git a/src/libsyntax_ext/proc_macro_server.rs b/src/libsyntax_ext/proc_macro_server.rs
index 6c7da589a4257..a04d6c92b7817 100644
--- a/src/libsyntax_ext/proc_macro_server.rs
+++ b/src/libsyntax_ext/proc_macro_server.rs
@@ -64,11 +64,11 @@ impl FromInternal<(TokenStream, &'_ ParseSess, &'_ mut Vec<Self>)>
 
         let (tree, joint) = stream.as_tree();
         let (span, token) = match tree {
-            tokenstream::TokenTree::Delimited(span, delimed) => {
-                let delimiter = Delimiter::from_internal(delimed.delim);
+            tokenstream::TokenTree::Delimited(span, delim, tts) => {
+                let delimiter = Delimiter::from_internal(delim);
                 return TokenTree::Group(Group {
                     delimiter,
-                    stream: delimed.tts.into(),
+                    stream: tts.into(),
                     span,
                 });
             }
@@ -232,10 +232,8 @@ impl ToInternal<TokenStream> for TokenTree<Group, Punct, Ident, Literal> {
             }) => {
                 return tokenstream::TokenTree::Delimited(
                     span,
-                    tokenstream::Delimited {
-                        delim: delimiter.to_internal(),
-                        tts: stream.into(),
-                    },
+                    delimiter.to_internal(),
+                    stream.into(),
                 )
                 .into();
             }