libsyntax: De-`@str` literal strings in the AST

22 files changed, 219 insertions, 113 deletions

diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index f7e474f666c..7416e213792 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -722,7 +722,7 @@ pub type Lit = Spanned<Lit_>;
 
 #[deriving(Clone, Eq, Encodable, Decodable, IterBytes)]
 pub enum Lit_ {
-    LitStr(@str, StrStyle),
+    LitStr(InternedString, StrStyle),
     LitBinary(@[u8]),
     LitChar(u32),
     LitInt(i64, IntTy),
diff --git a/src/libsyntax/attr.rs b/src/libsyntax/attr.rs
index 6c6f47bae8a..78e9d3bd46f 100644
--- a/src/libsyntax/attr.rs
+++ b/src/libsyntax/attr.rs
@@ -17,6 +17,7 @@ use codemap::BytePos;
 use diagnostic::SpanHandler;
 use parse::comments::{doc_comment_style, strip_doc_comment_decoration};
 use parse::token::InternedString;
+use parse::token;
 use crateid::CrateId;
 
 use std::hashmap::HashSet;
@@ -34,7 +35,7 @@ pub trait AttrMetaMethods {
      * Gets the string value if self is a MetaNameValue variant
      * containing a string, otherwise None.
      */
-    fn value_str(&self) -> Option<@str>;
+    fn value_str(&self) -> Option<InternedString>;
     /// Gets a list of inner meta items from a list MetaItem type.
     fn meta_item_list<'a>(&'a self) -> Option<&'a [@MetaItem]>;
 
@@ -42,16 +43,18 @@ pub trait AttrMetaMethods {
      * If the meta item is a name-value type with a string value then returns
      * a tuple containing the name and string value, otherwise `None`
      */
-    fn name_str_pair(&self) -> Option<(InternedString, @str)>;
+    fn name_str_pair(&self) -> Option<(InternedString,InternedString)>;
 }
 
 impl AttrMetaMethods for Attribute {
     fn name(&self) -> InternedString { self.meta().name() }
-    fn value_str(&self) -> Option<@str> { self.meta().value_str() }
+    fn value_str(&self) -> Option<InternedString> {
+        self.meta().value_str()
+    }
     fn meta_item_list<'a>(&'a self) -> Option<&'a [@MetaItem]> {
         self.node.value.meta_item_list()
     }
-    fn name_str_pair(&self) -> Option<(InternedString, @str)> {
+    fn name_str_pair(&self) -> Option<(InternedString,InternedString)> {
         self.meta().name_str_pair()
     }
 }
@@ -65,11 +68,11 @@ impl AttrMetaMethods for MetaItem {
         }
     }
 
-    fn value_str(&self) -> Option<@str> {
+    fn value_str(&self) -> Option<InternedString> {
         match self.node {
             MetaNameValue(_, ref v) => {
                 match v.node {
-                    ast::LitStr(s, _) => Some(s),
+                    ast::LitStr(ref s, _) => Some((*s).clone()),
                     _ => None,
                 }
             },
@@ -84,7 +87,7 @@ impl AttrMetaMethods for MetaItem {
         }
     }
 
-    fn name_str_pair(&self) -> Option<(InternedString, @str)> {
+    fn name_str_pair(&self) -> Option<(InternedString,InternedString)> {
         self.value_str().map(|s| (self.name(), s))
     }
 }
@@ -92,11 +95,11 @@ impl AttrMetaMethods for MetaItem {
 // Annoying, but required to get test_cfg to work
 impl AttrMetaMethods for @MetaItem {
     fn name(&self) -> InternedString { (**self).name() }
-    fn value_str(&self) -> Option<@str> { (**self).value_str() }
+    fn value_str(&self) -> Option<InternedString> { (**self).value_str() }
     fn meta_item_list<'a>(&'a self) -> Option<&'a [@MetaItem]> {
         (**self).meta_item_list()
     }
-    fn name_str_pair(&self) -> Option<(InternedString, @str)> {
+    fn name_str_pair(&self) -> Option<(InternedString,InternedString)> {
         (**self).name_str_pair()
     }
 }
@@ -119,8 +122,10 @@ impl AttributeMethods for Attribute {
     fn desugar_doc(&self) -> Attribute {
         if self.node.is_sugared_doc {
             let comment = self.value_str().unwrap();
-            let meta = mk_name_value_item_str(InternedString::new("doc"),
-                                              strip_doc_comment_decoration(comment).to_managed());
+            let meta = mk_name_value_item_str(
+                InternedString::new("doc"),
+                token::intern_and_get_ident(strip_doc_comment_decoration(
+                        comment.get())));
             mk_attr(meta)
         } else {
             *self
@@ -130,7 +135,7 @@ impl AttributeMethods for Attribute {
 
 /* Constructors */
 
-pub fn mk_name_value_item_str(name: InternedString, value: @str)
+pub fn mk_name_value_item_str(name: InternedString, value: InternedString)
                               -> @MetaItem {
     let value_lit = dummy_spanned(ast::LitStr(value, ast::CookedStr));
     mk_name_value_item(name, value_lit)
@@ -157,8 +162,9 @@ pub fn mk_attr(item: @MetaItem) -> Attribute {
     })
 }
 
-pub fn mk_sugared_doc_attr(text: @str, lo: BytePos, hi: BytePos) -> Attribute {
-    let style = doc_comment_style(text);
+pub fn mk_sugared_doc_attr(text: InternedString, lo: BytePos, hi: BytePos)
+                           -> Attribute {
+    let style = doc_comment_style(text.get());
     let lit = spanned(lo, hi, ast::LitStr(text, ast::CookedStr));
     let attr = Attribute_ {
         style: style,
@@ -191,14 +197,14 @@ pub fn contains_name<AM: AttrMetaMethods>(metas: &[AM], name: &str) -> bool {
 }
 
 pub fn first_attr_value_str_by_name(attrs: &[Attribute], name: &str)
-                                 -> Option<@str> {
+                                 -> Option<InternedString> {
     attrs.iter()
         .find(|at| at.name().equiv(&name))
         .and_then(|at| at.value_str())
 }
 
 pub fn last_meta_item_value_str_by_name(items: &[@MetaItem], name: &str)
-                                     -> Option<@str> {
+                                     -> Option<InternedString> {
     items.rev_iter()
          .find(|mi| mi.name().equiv(&name))
          .and_then(|i| i.value_str())
@@ -247,7 +253,7 @@ pub fn find_linkage_metas(attrs: &[Attribute]) -> ~[@MetaItem] {
 pub fn find_crateid(attrs: &[Attribute]) -> Option<CrateId> {
     match first_attr_value_str_by_name(attrs, "crate_id") {
         None => None,
-        Some(id) => from_str::<CrateId>(id),
+        Some(id) => from_str::<CrateId>(id.get()),
     }
 }
 
@@ -331,7 +337,7 @@ pub fn test_cfg<AM: AttrMetaMethods, It: Iterator<AM>>
 /// Represents the #[deprecated="foo"] (etc) attributes.
 pub struct Stability {
     level: StabilityLevel,
-    text: Option<@str>
+    text: Option<InternedString>
 }
 
 /// The available stability levels.
@@ -346,7 +352,8 @@ pub enum StabilityLevel {
 }
 
 /// Find the first stability attribute. `None` if none exists.
-pub fn find_stability<AM: AttrMetaMethods, It: Iterator<AM>>(mut metas: It) -> Option<Stability> {
+pub fn find_stability<AM: AttrMetaMethods, It: Iterator<AM>>(mut metas: It)
+                      -> Option<Stability> {
     for m in metas {
         let level = match m.name().get() {
             "deprecated" => Deprecated,
diff --git a/src/libsyntax/ext/asm.rs b/src/libsyntax/ext/asm.rs
index 021f0d29d9e..babf0f13874 100644
--- a/src/libsyntax/ext/asm.rs
+++ b/src/libsyntax/ext/asm.rs
@@ -17,6 +17,7 @@ use codemap::Span;
 use ext::base;
 use ext::base::*;
 use parse;
+use parse::token::InternedString;
 use parse::token;
 
 enum State {
@@ -43,7 +44,7 @@ pub fn expand_asm(cx: &mut ExtCtxt, sp: Span, tts: &[ast::TokenTree])
                                            cx.cfg(),
                                            tts.to_owned());
 
-    let mut asm = @"";
+    let mut asm = InternedString::new("");
     let mut asm_str_style = None;
     let mut outputs = ~[];
     let mut inputs = ~[];
@@ -191,7 +192,7 @@ pub fn expand_asm(cx: &mut ExtCtxt, sp: Span, tts: &[ast::TokenTree])
     MRExpr(@ast::Expr {
         id: ast::DUMMY_NODE_ID,
         node: ast::ExprInlineAsm(ast::InlineAsm {
-            asm: asm,
+            asm: asm.get().to_managed(),
             asm_str_style: asm_str_style.unwrap(),
             clobbers: cons.to_managed(),
             inputs: inputs,
diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs
index adf1eabf9d9..eda0a47148a 100644
--- a/src/libsyntax/ext/base.rs
+++ b/src/libsyntax/ext/base.rs
@@ -16,7 +16,7 @@ use ext;
 use ext::expand;
 use parse;
 use parse::token;
-use parse::token::{ident_to_str, intern, str_to_ident};
+use parse::token::{InternedString, ident_to_str, intern, str_to_ident};
 use util::small_vector::SmallVector;
 
 use std::hashmap::HashMap;
@@ -407,11 +407,11 @@ impl<'a> ExtCtxt<'a> {
 /// Extract a string literal from `expr`, emitting `err_msg` if `expr`
 /// is not a string literal. This does not stop compilation on error,
 /// merely emits a non-fatal error and returns None.
-pub fn expr_to_str(cx: &ExtCtxt, expr: @ast::Expr,
-                   err_msg: &str) -> Option<(@str, ast::StrStyle)> {
+pub fn expr_to_str(cx: &ExtCtxt, expr: @ast::Expr, err_msg: &str)
+                   -> Option<(InternedString, ast::StrStyle)> {
     match expr.node {
         ast::ExprLit(l) => match l.node {
-            ast::LitStr(s, style) => return Some((s, style)),
+            ast::LitStr(s, style) => return Some(((*s).clone(), style)),
             _ => cx.span_err(l.span, err_msg)
         },
         _ => cx.span_err(expr.span, err_msg)
@@ -424,7 +424,9 @@ pub fn expr_to_str(cx: &ExtCtxt, expr: @ast::Expr,
 /// compilation should call
 /// `cx.parse_sess.span_diagnostic.abort_if_errors()` (this should be
 /// done as rarely as possible).
-pub fn check_zero_tts(cx: &ExtCtxt, sp: Span, tts: &[ast::TokenTree],
+pub fn check_zero_tts(cx: &ExtCtxt,
+                      sp: Span,
+                      tts: &[ast::TokenTree],
                       name: &str) {
     if tts.len() != 0 {
         cx.span_err(sp, format!("{} takes no arguments", name));
diff --git a/src/libsyntax/ext/build.rs b/src/libsyntax/ext/build.rs
index 884bd831ce8..c5ee1948466 100644
--- a/src/libsyntax/ext/build.rs
+++ b/src/libsyntax/ext/build.rs
@@ -19,6 +19,7 @@ use fold::Folder;
 use opt_vec;
 use opt_vec::OptVec;
 use parse::token::special_idents;
+use parse::token;
 
 pub struct Field {
     ident: ast::Ident,
@@ -134,13 +135,13 @@ pub trait AstBuilder {
     fn expr_vec(&self, sp: Span, exprs: ~[@ast::Expr]) -> @ast::Expr;
     fn expr_vec_uniq(&self, sp: Span, exprs: ~[@ast::Expr]) -> @ast::Expr;
     fn expr_vec_slice(&self, sp: Span, exprs: ~[@ast::Expr]) -> @ast::Expr;
-    fn expr_str(&self, sp: Span, s: @str) -> @ast::Expr;
-    fn expr_str_uniq(&self, sp: Span, s: @str) -> @ast::Expr;
+    fn expr_str(&self, sp: Span, s: InternedString) -> @ast::Expr;
+    fn expr_str_uniq(&self, sp: Span, s: InternedString) -> @ast::Expr;
 
     fn expr_some(&self, sp: Span, expr: @ast::Expr) -> @ast::Expr;
     fn expr_none(&self, sp: Span) -> @ast::Expr;
 
-    fn expr_fail(&self, span: Span, msg: @str) -> @ast::Expr;
+    fn expr_fail(&self, span: Span, msg: InternedString) -> @ast::Expr;
     fn expr_unreachable(&self, span: Span) -> @ast::Expr;
 
     fn pat(&self, span: Span, pat: ast::Pat_) -> @ast::Pat;
@@ -589,10 +590,10 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
     fn expr_vec_slice(&self, sp: Span, exprs: ~[@ast::Expr]) -> @ast::Expr {
         self.expr_vstore(sp, self.expr_vec(sp, exprs), ast::ExprVstoreSlice)
     }
-    fn expr_str(&self, sp: Span, s: @str) -> @ast::Expr {
+    fn expr_str(&self, sp: Span, s: InternedString) -> @ast::Expr {
         self.expr_lit(sp, ast::LitStr(s, ast::CookedStr))
     }
-    fn expr_str_uniq(&self, sp: Span, s: @str) -> @ast::Expr {
+    fn expr_str_uniq(&self, sp: Span, s: InternedString) -> @ast::Expr {
         self.expr_vstore(sp, self.expr_str(sp, s), ast::ExprVstoreUniq)
     }
 
@@ -620,7 +621,7 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
         self.expr_path(none)
     }
 
-    fn expr_fail(&self, span: Span, msg: @str) -> @ast::Expr {
+    fn expr_fail(&self, span: Span, msg: InternedString) -> @ast::Expr {
         let loc = self.codemap().lookup_char_pos(span.lo);
         self.expr_call_global(
             span,
@@ -631,13 +632,16 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
             ],
             ~[
                 self.expr_str(span, msg),
-                self.expr_str(span, loc.file.name),
+                self.expr_str(span,
+                              token::intern_and_get_ident(loc.file.name)),
                 self.expr_uint(span, loc.line),
             ])
     }
 
     fn expr_unreachable(&self, span: Span) -> @ast::Expr {
-        self.expr_fail(span, @"internal error: entered unreachable code")
+        self.expr_fail(span,
+                       InternedString::new(
+                           "internal error: entered unreachable code"))
     }
 
 
diff --git a/src/libsyntax/ext/bytes.rs b/src/libsyntax/ext/bytes.rs
index 0c9a23be558..6852a0cec33 100644
--- a/src/libsyntax/ext/bytes.rs
+++ b/src/libsyntax/ext/bytes.rs
@@ -31,8 +31,8 @@ pub fn expand_syntax_ext(cx: &mut ExtCtxt, sp: Span, tts: &[ast::TokenTree]) ->
             // expression is a literal
             ast::ExprLit(lit) => match lit.node {
                 // string literal, push each byte to vector expression
-                ast::LitStr(s, _) => {
-                    for byte in s.bytes() {
+                ast::LitStr(ref s, _) => {
+                    for byte in s.get().bytes() {
                         bytes.push(cx.expr_u8(expr.span, byte));
                     }
                 }
diff --git a/src/libsyntax/ext/concat.rs b/src/libsyntax/ext/concat.rs
index 2a68674af95..f570ca4c1bf 100644
--- a/src/libsyntax/ext/concat.rs
+++ b/src/libsyntax/ext/concat.rs
@@ -14,6 +14,7 @@ use ast;
 use codemap;
 use ext::base;
 use ext::build::AstBuilder;
+use parse::token;
 
 pub fn expand_syntax_ext(cx: &mut base::ExtCtxt,
                          sp: codemap::Span,
@@ -28,8 +29,10 @@ pub fn expand_syntax_ext(cx: &mut base::ExtCtxt,
         match e.node {
             ast::ExprLit(lit) => {
                 match lit.node {
-                    ast::LitStr(s, _) | ast::LitFloat(s, _)
-                    | ast::LitFloatUnsuffixed(s) => {
+                    ast::LitStr(ref s, _) => {
+                        accumulator.push_str(s.get());
+                    }
+                    ast::LitFloat(s, _) | ast::LitFloatUnsuffixed(s) => {
                         accumulator.push_str(s);
                     }
                     ast::LitChar(c) => {
@@ -55,5 +58,5 @@ pub fn expand_syntax_ext(cx: &mut base::ExtCtxt,
             }
         }
     }
-    return base::MRExpr(cx.expr_str(sp, accumulator.to_managed()));
+    base::MRExpr(cx.expr_str(sp, token::intern_and_get_ident(accumulator)))
 }
diff --git a/src/libsyntax/ext/deriving/decodable.rs b/src/libsyntax/ext/deriving/decodable.rs
index a9268d85c91..019a4dfe7cc 100644
--- a/src/libsyntax/ext/deriving/decodable.rs
+++ b/src/libsyntax/ext/deriving/decodable.rs
@@ -18,6 +18,8 @@ use codemap::Span;
 use ext::base::ExtCtxt;
 use ext::build::AstBuilder;
 use ext::deriving::generic::*;
+use parse::token::InternedString;
+use parse::token;
 
 pub fn expand_deriving_decodable(cx: &ExtCtxt,
                                  span: Span,
@@ -82,10 +84,15 @@ fn decodable_substructure(cx: &ExtCtxt, trait_span: Span,
                                       cx.expr_uint(span, field),
                                       lambdadecode])
             });
-            cx.expr_method_call(trait_span, decoder, cx.ident_of("read_struct"),
-                                ~[cx.expr_str(trait_span, cx.str_of(substr.type_ident)),
-                                  cx.expr_uint(trait_span, nfields),
-                                  cx.lambda_expr_1(trait_span, result, blkarg)])
+            cx.expr_method_call(trait_span,
+                                decoder,
+                                cx.ident_of("read_struct"),
+                                ~[
+                cx.expr_str(trait_span,
+                            token::get_ident(substr.type_ident.name)),
+                cx.expr_uint(trait_span, nfields),
+                cx.lambda_expr_1(trait_span, result, blkarg)
+            ])
         }
         StaticEnum(_, ref fields) => {
             let variant = cx.ident_of("i");
@@ -95,7 +102,8 @@ fn decodable_substructure(cx: &ExtCtxt, trait_span: Span,
             let rvariant_arg = cx.ident_of("read_enum_variant_arg");
 
             for (i, &(name, v_span, ref parts)) in fields.iter().enumerate() {
-                variants.push(cx.expr_str(v_span, cx.str_of(name)));
+                variants.push(cx.expr_str(v_span,
+                                          token::get_ident(name.name)));
 
                 let decoded = decode_static_fields(cx,
                                                    v_span,
@@ -120,9 +128,14 @@ fn decodable_substructure(cx: &ExtCtxt, trait_span: Span,
             let result = cx.expr_method_call(trait_span, blkdecoder,
                                              cx.ident_of("read_enum_variant"),
                                              ~[variant_vec, lambda]);
-            cx.expr_method_call(trait_span, decoder, cx.ident_of("read_enum"),
-                                ~[cx.expr_str(trait_span, cx.str_of(substr.type_ident)),
-                                  cx.lambda_expr_1(trait_span, result, blkarg)])
+            cx.expr_method_call(trait_span,
+                                decoder,
+                                cx.ident_of("read_enum"),
+                                ~[
+                cx.expr_str(trait_span,
+                            token::get_ident(substr.type_ident.name)),
+                cx.lambda_expr_1(trait_span, result, blkarg)
+            ])
         }
         _ => cx.bug("expected StaticEnum or StaticStruct in deriving(Decodable)")
     };
@@ -135,7 +148,7 @@ fn decode_static_fields(cx: &ExtCtxt,
                         trait_span: Span,
                         outer_pat_ident: Ident,
                         fields: &StaticFields,
-                        getarg: |Span, @str, uint| -> @Expr)
+                        getarg: |Span, InternedString, uint| -> @Expr)
                         -> @Expr {
     match *fields {
         Unnamed(ref fields) => {
@@ -143,7 +156,10 @@ fn decode_static_fields(cx: &ExtCtxt,
                 cx.expr_ident(trait_span, outer_pat_ident)
             } else {
                 let fields = fields.iter().enumerate().map(|(i, &span)| {
-                    getarg(span, format!("_field{}", i).to_managed(), i)
+                    getarg(span,
+                           token::intern_and_get_ident(format!("_field{}",
+                                                               i)),
+                           i)
                 }).collect();
 
                 cx.expr_call_ident(trait_span, outer_pat_ident, fields)
@@ -152,7 +168,9 @@ fn decode_static_fields(cx: &ExtCtxt,
         Named(ref fields) => {
             // use the field's span to get nicer error messages.
             let fields = fields.iter().enumerate().map(|(i, &(name, span))| {
-                cx.field_imm(span, name, getarg(span, cx.str_of(name), i))
+                cx.field_imm(span,
+                             name,
+                             getarg(span, token::get_ident(name.name), i))
             }).collect();
             cx.expr_struct_ident(trait_span, outer_pat_ident, fields)
         }
diff --git a/src/libsyntax/ext/deriving/encodable.rs b/src/libsyntax/ext/deriving/encodable.rs
index 9a8861f2e70..1dfc5b59e06 100644
--- a/src/libsyntax/ext/deriving/encodable.rs
+++ b/src/libsyntax/ext/deriving/encodable.rs
@@ -80,6 +80,7 @@ use codemap::Span;
 use ext::base::ExtCtxt;
 use ext::build::AstBuilder;
 use ext::deriving::generic::*;
+use parse::token;
 
 pub fn expand_deriving_encodable(cx: &ExtCtxt,
                                  span: Span,
@@ -125,10 +126,17 @@ fn encodable_substructure(cx: &ExtCtxt, trait_span: Span,
         Struct(ref fields) => {
             let emit_struct_field = cx.ident_of("emit_struct_field");
             let mut stmts = ~[];
-            for (i, &FieldInfo { name, self_, span, .. }) in fields.iter().enumerate() {
+            for (i, &FieldInfo {
+                    name,
+                    self_,
+                    span,
+                    ..
+                }) in fields.iter().enumerate() {
                 let name = match name {
-                    Some(id) => cx.str_of(id),
-                    None => format!("_field{}", i).to_managed()
+                    Some(id) => token::get_ident(id),
+                    None => {
+                        token::intern_and_get_ident(format!("_field{}", i))
+                    }
                 };
                 let enc = cx.expr_method_call(span, self_, encode, ~[blkencoder]);
                 let lambda = cx.lambda_expr_1(span, enc, blkarg);
@@ -141,10 +149,15 @@ fn encodable_substructure(cx: &ExtCtxt, trait_span: Span,
             }
 
             let blk = cx.lambda_stmts_1(trait_span, stmts, blkarg);
-            cx.expr_method_call(trait_span, encoder, cx.ident_of("emit_struct"),
-                                ~[cx.expr_str(trait_span, cx.str_of(substr.type_ident)),
-                                  cx.expr_uint(trait_span, fields.len()),
-                                  blk])
+            cx.expr_method_call(trait_span,
+                                encoder,
+                                cx.ident_of("emit_struct"),
+                                ~[
+                cx.expr_str(trait_span,
+                            token::get_ident(substr.type_ident.name)),
+                cx.expr_uint(trait_span, fields.len()),
+                blk
+            ])
         }
 
         EnumMatching(idx, variant, ref fields) => {
@@ -167,7 +180,8 @@ fn encodable_substructure(cx: &ExtCtxt, trait_span: Span,
             }
 
             let blk = cx.lambda_stmts_1(trait_span, stmts, blkarg);
-            let name = cx.expr_str(trait_span, cx.str_of(variant.node.name));
+            let name = cx.expr_str(trait_span,
+                                   token::get_ident(variant.node.name));
             let call = cx.expr_method_call(trait_span, blkencoder,
                                            cx.ident_of("emit_enum_variant"),
                                            ~[name,
@@ -175,11 +189,14 @@ fn encodable_substructure(cx: &ExtCtxt, trait_span: Span,
                                              cx.expr_uint(trait_span, fields.len()),
                                              blk]);
             let blk = cx.lambda_expr_1(trait_span, call, blkarg);
-            let ret = cx.expr_method_call(trait_span, encoder,
+            let ret = cx.expr_method_call(trait_span,
+                                          encoder,
                                           cx.ident_of("emit_enum"),
-                                          ~[cx.expr_str(trait_span,
-                                            cx.str_of(substr.type_ident)),
-                                            blk]);
+                                          ~[
+                cx.expr_str(trait_span,
+                            token::get_ident(substr.type_ident.name)),
+                blk
+            ]);
             cx.expr_block(cx.block(trait_span, ~[me], Some(ret)))
         }
 
diff --git a/src/libsyntax/ext/deriving/generic.rs b/src/libsyntax/ext/deriving/generic.rs
index 20a515692e1..45e3be7f23d 100644
--- a/src/libsyntax/ext/deriving/generic.rs
+++ b/src/libsyntax/ext/deriving/generic.rs
@@ -185,6 +185,7 @@ use codemap;
 use codemap::Span;
 use opt_vec;
 use parse::token::InternedString;
+use parse::token;
 
 use std::vec;
 
@@ -398,7 +399,9 @@ impl<'a> TraitDef<'a> {
             self.span,
             cx.meta_name_value(self.span,
                                InternedString::new("doc"),
-                               ast::LitStr(@"Automatically derived.", ast::CookedStr)));
+                               ast::LitStr(token::intern_and_get_ident(
+                                       "Automatically derived."),
+                                       ast::CookedStr)));
         cx.item(
             self.span,
             ::parse::token::special_idents::clownshoes_extensions,
diff --git a/src/libsyntax/ext/deriving/primitive.rs b/src/libsyntax/ext/deriving/primitive.rs
index a4e606f53c0..e2f72e87085 100644
--- a/src/libsyntax/ext/deriving/primitive.rs
+++ b/src/libsyntax/ext/deriving/primitive.rs
@@ -14,6 +14,7 @@ use codemap::Span;
 use ext::base::ExtCtxt;
 use ext::build::AstBuilder;
 use ext::deriving::generic::*;
+use parse::token::InternedString;
 
 pub fn expand_deriving_from_primitive(cx: &ExtCtxt,
                                       span: Span,
@@ -73,13 +74,13 @@ fn cs_from(name: &str, cx: &ExtCtxt, trait_span: Span, substr: &Substructure) ->
     match *substr.fields {
         StaticStruct(..) => {
             cx.span_err(trait_span, "`FromPrimitive` cannot be derived for structs");
-            return cx.expr_fail(trait_span, @"");
+            return cx.expr_fail(trait_span, InternedString::new(""));
         }
         StaticEnum(enum_def, _) => {
             if enum_def.variants.is_empty() {
                 cx.span_err(trait_span,
                             "`FromPrimitive` cannot be derived for enums with no variants");
-                return cx.expr_fail(trait_span, @"");
+                return cx.expr_fail(trait_span, InternedString::new(""));
             }
 
             let mut arms = ~[];
@@ -91,7 +92,8 @@ fn cs_from(name: &str, cx: &ExtCtxt, trait_span: Span, substr: &Substructure) ->
                             cx.span_err(trait_span,
                                         "`FromPrimitive` cannot be derived for \
                                         enum variants with arguments");
-                            return cx.expr_fail(trait_span, @"");
+                            return cx.expr_fail(trait_span,
+                                                InternedString::new(""));
                         }
                         let span = variant.span;
 
@@ -117,7 +119,8 @@ fn cs_from(name: &str, cx: &ExtCtxt, trait_span: Span, substr: &Substructure) ->
                         cx.span_err(trait_span,
                                     "`FromPrimitive` cannot be derived for enums \
                                     with struct variants");
-                        return cx.expr_fail(trait_span, @"");
+                        return cx.expr_fail(trait_span,
+                                            InternedString::new(""));
                     }
                 }
             }
diff --git a/src/libsyntax/ext/deriving/to_str.rs b/src/libsyntax/ext/deriving/to_str.rs
index 81453a5a10b..97412595b29 100644
--- a/src/libsyntax/ext/deriving/to_str.rs
+++ b/src/libsyntax/ext/deriving/to_str.rs
@@ -14,6 +14,8 @@ use codemap::Span;
 use ext::base::ExtCtxt;
 use ext::build::AstBuilder;
 use ext::deriving::generic::*;
+use parse::token::InternedString;
+use parse::token;
 
 pub fn expand_deriving_to_str(cx: &ExtCtxt,
                               span: Span,
@@ -47,18 +49,20 @@ pub fn expand_deriving_to_str(cx: &ExtCtxt,
 // doesn't invoke the to_str() method on each field. Hence we mirror
 // the logic of the repr_to_str() method, but with tweaks to call to_str()
 // on sub-fields.
-fn to_str_substructure(cx: &ExtCtxt, span: Span,
-                       substr: &Substructure) -> @Expr {
+fn to_str_substructure(cx: &ExtCtxt, span: Span, substr: &Substructure)
+                       -> @Expr {
     let to_str = cx.ident_of("to_str");
 
-    let doit = |start: &str, end: @str, name: ast::Ident,
+    let doit = |start: &str,
+                end: InternedString,
+                name: ast::Ident,
                 fields: &[FieldInfo]| {
         if fields.len() == 0 {
-            cx.expr_str_uniq(span, cx.str_of(name))
+            cx.expr_str_uniq(span, token::get_ident(name.name))
         } else {
             let buf = cx.ident_of("buf");
-            let start = cx.str_of(name) + start;
-            let init = cx.expr_str_uniq(span, start.to_managed());
+            let start = token::intern_and_get_ident(cx.str_of(name) + start);
+            let init = cx.expr_str_uniq(span, start);
             let mut stmts = ~[cx.stmt_let(span, true, buf, init)];
             let push_str = cx.ident_of("push_str");
 
@@ -70,38 +74,52 @@ fn to_str_substructure(cx: &ExtCtxt, span: Span,
 
             for (i, &FieldInfo {name, span, self_, .. }) in fields.iter().enumerate() {
                 if i > 0 {
-                    push(cx.expr_str(span, @", "));
+                    push(cx.expr_str(span, InternedString::new(", ")));
                 }
                 match name {
                     None => {}
                     Some(id) => {
                         let name = cx.str_of(id) + ": ";
-                        push(cx.expr_str(span, name.to_managed()));
+                        push(cx.expr_str(span,
+                                         token::intern_and_get_ident(name)));
                     }
                 }
                 push(cx.expr_method_call(span, self_, to_str, ~[]));
             }
             push(cx.expr_str(span, end));
 
-            cx.expr_block(cx.block(span, stmts, Some(cx.expr_ident(span, buf))))
+            cx.expr_block(cx.block(span, stmts, Some(cx.expr_ident(span,
+                                                                   buf))))
         }
     };
 
     return match *substr.fields {
         Struct(ref fields) => {
             if fields.len() == 0 || fields[0].name.is_none() {
-                doit("(", @")", substr.type_ident, *fields)
+                doit("(",
+                     InternedString::new(")"),
+                     substr.type_ident,
+                     *fields)
             } else {
-                doit("{", @"}", substr.type_ident, *fields)
+                doit("{",
+                     InternedString::new("}"),
+                     substr.type_ident,
+                     *fields)
             }
         }
 
         EnumMatching(_, variant, ref fields) => {
             match variant.node.kind {
                 ast::TupleVariantKind(..) =>
-                    doit("(", @")", variant.node.name, *fields),
+                    doit("(",
+                         InternedString::new(")"),
+                         variant.node.name,
+                         *fields),
                 ast::StructVariantKind(..) =>
-                    doit("{", @"}", variant.node.name, *fields),
+                    doit("{",
+                         InternedString::new("}"),
+                         variant.node.name,
+                         *fields),
             }
         }
 
diff --git a/src/libsyntax/ext/env.rs b/src/libsyntax/ext/env.rs
index a9b40ea7ec6..c23a1ce1e28 100644
--- a/src/libsyntax/ext/env.rs
+++ b/src/libsyntax/ext/env.rs
@@ -19,6 +19,7 @@ use codemap::Span;
 use ext::base::*;
 use ext::base;
 use ext::build::AstBuilder;
+use parse::token;
 
 use std::os;
 
@@ -52,7 +53,11 @@ pub fn expand_env(cx: &mut ExtCtxt, sp: Span, tts: &[ast::TokenTree])
         Some((v, _style)) => v
     };
     let msg = match exprs.len() {
-        1 => format!("environment variable `{}` not defined", var).to_managed(),
+        1 => {
+            token::intern_and_get_ident(format!("environment variable `{}` \
+                                                 not defined",
+                                                var))
+        }
         2 => {
             match expr_to_str(cx, exprs[1], "expected string literal") {
                 None => return MacResult::dummy_expr(),
@@ -65,12 +70,12 @@ pub fn expand_env(cx: &mut ExtCtxt, sp: Span, tts: &[ast::TokenTree])
         }
     };
 
-    let e = match os::getenv(var) {
+    let e = match os::getenv(var.get()) {
         None => {
-            cx.span_err(sp, msg);
+            cx.span_err(sp, msg.get());
             cx.expr_uint(sp, 0)
         }
-        Some(s) => cx.expr_str(sp, s.to_managed())
+        Some(s) => cx.expr_str(sp, token::intern_and_get_ident(s))
     };
     MRExpr(e)
 }
diff --git a/src/libsyntax/ext/format.rs b/src/libsyntax/ext/format.rs
index 5730d435c15..5bedb1a887e 100644
--- a/src/libsyntax/ext/format.rs
+++ b/src/libsyntax/ext/format.rs
@@ -416,7 +416,7 @@ impl<'a> Context<'a> {
                         let result = arm.result.iter().map(|p| {
                             self.trans_piece(p)
                         }).collect();
-                        let s = arm.selector.to_managed();
+                        let s = token::intern_and_get_ident(arm.selector);
                         let selector = self.ecx.expr_str(sp, s);
                         self.ecx.expr_struct(sp, p, ~[
                             self.ecx.field_imm(sp,
@@ -492,8 +492,12 @@ impl<'a> Context<'a> {
 
         match *piece {
             parse::String(s) => {
-                self.ecx.expr_call_global(sp, rtpath("String"),
-                                          ~[self.ecx.expr_str(sp, s.to_managed())])
+                let s = token::intern_and_get_ident(s);
+                self.ecx.expr_call_global(sp,
+                                          rtpath("String"),
+                                          ~[
+                    self.ecx.expr_str(sp, s)
+                ])
             }
             parse::CurrentArgument => {
                 let nil = self.ecx.expr_lit(sp, ast::LitNil);
@@ -763,8 +767,9 @@ pub fn expand_args(ecx: &mut ExtCtxt, sp: Span,
     // Be sure to recursively expand macros just in case the format string uses
     // a macro to build the format expression.
     let expr = cx.ecx.expand_expr(efmt);
-    let fmt = match expr_to_str(cx.ecx, expr,
-                                     "format argument must be a string literal.") {
+    let fmt = match expr_to_str(cx.ecx,
+                                expr,
+                                "format argument must be a string literal.") {
         Some((fmt, _)) => fmt,
         None => return MacResult::dummy_expr()
     };
@@ -776,7 +781,7 @@ pub fn expand_args(ecx: &mut ExtCtxt, sp: Span,
             cx.ecx.span_err(efmt.span, m);
         }
     }).inside(|| {
-        for piece in parse::Parser::new(fmt) {
+        for piece in parse::Parser::new(fmt.get()) {
             if !err {
                 cx.verify_piece(&piece);
                 let piece = cx.trans_piece(&piece);
diff --git a/src/libsyntax/ext/quote.rs b/src/libsyntax/ext/quote.rs
index 6faed270875..425ac8865b2 100644
--- a/src/libsyntax/ext/quote.rs
+++ b/src/libsyntax/ext/quote.rs
@@ -31,6 +31,7 @@ use parse;
 pub mod rt {
     use ast;
     use ext::base::ExtCtxt;
+    use parse::token;
     use parse;
     use print::pprust;
 
@@ -118,7 +119,8 @@ pub mod rt {
 
     impl<'a> ToSource for &'a str {
         fn to_source(&self) -> @str {
-            let lit = dummy_spanned(ast::LitStr(self.to_managed(), ast::CookedStr));
+            let lit = dummy_spanned(ast::LitStr(
+                    token::intern_and_get_ident(*self), ast::CookedStr));
             pprust::lit_to_str(&lit).to_managed()
         }
     }
@@ -349,7 +351,7 @@ fn id_ext(str: &str) -> ast::Ident {
 
 // Lift an ident to the expr that evaluates to that ident.
 fn mk_ident(cx: &ExtCtxt, sp: Span, ident: ast::Ident) -> @ast::Expr {
-    let e_str = cx.expr_str(sp, cx.str_of(ident));
+    let e_str = cx.expr_str(sp, token::get_ident(ident.name));
     cx.expr_method_call(sp,
                         cx.expr_ident(sp, id_ext("ext_cx")),
                         id_ext("ident_of"),
diff --git a/src/libsyntax/ext/source_util.rs b/src/libsyntax/ext/source_util.rs
index a9f94da7a98..b67f3ed263e 100644
--- a/src/libsyntax/ext/source_util.rs
+++ b/src/libsyntax/ext/source_util.rs
@@ -16,7 +16,8 @@ use ext::base::*;
 use ext::base;
 use ext::build::AstBuilder;
 use parse;
-use parse::token::{get_ident_interner};
+use parse::token::get_ident_interner;
+use parse::token;
 use print::pprust;
 
 use std::io;
@@ -57,21 +58,21 @@ pub fn expand_file(cx: &mut ExtCtxt, sp: Span, tts: &[ast::TokenTree])
 
     let topmost = topmost_expn_info(cx.backtrace().unwrap());
     let loc = cx.codemap().lookup_char_pos(topmost.call_site.lo);
-    let filename = loc.file.name;
+    let filename = token::intern_and_get_ident(loc.file.name);
     base::MRExpr(cx.expr_str(topmost.call_site, filename))
 }
 
 pub fn expand_stringify(cx: &mut ExtCtxt, sp: Span, tts: &[ast::TokenTree])
     -> base::MacResult {
     let s = pprust::tts_to_str(tts, get_ident_interner());
-    base::MRExpr(cx.expr_str(sp, s.to_managed()))
+    base::MRExpr(cx.expr_str(sp, token::intern_and_get_ident(s)))
 }
 
 pub fn expand_mod(cx: &mut ExtCtxt, sp: Span, tts: &[ast::TokenTree])
     -> base::MacResult {
     base::check_zero_tts(cx, sp, tts, "module_path!");
-    base::MRExpr(cx.expr_str(sp,
-                             cx.mod_path().map(|x| cx.str_of(*x)).connect("::").to_managed()))
+    let string = cx.mod_path().map(|x| cx.str_of(*x)).connect("::");
+    base::MRExpr(cx.expr_str(sp, token::intern_and_get_ident(string)))
 }
 
 // include! : parse the given file as an expr
@@ -117,7 +118,7 @@ pub fn expand_include_str(cx: &mut ExtCtxt, sp: Span, tts: &[ast::TokenTree])
             let filename = file.display().to_str().to_managed();
             cx.parse_sess.cm.new_filemap(filename, src);
 
-            base::MRExpr(cx.expr_str(sp, src))
+            base::MRExpr(cx.expr_str(sp, token::intern_and_get_ident(src)))
         }
         None => {
             cx.span_err(sp, format!("{} wasn't a utf-8 file", file.display()));
diff --git a/src/libsyntax/fold.rs b/src/libsyntax/fold.rs
index c2d54a4f368..9a346e17d28 100644
--- a/src/libsyntax/fold.rs
+++ b/src/libsyntax/fold.rs
@@ -326,7 +326,9 @@ fn fold_meta_item_<T: Folder>(mi: @MetaItem, fld: &mut T) -> @MetaItem {
                     let fold_meta_item = |x| fold_meta_item_(x, fld);
                     MetaList((*id).clone(), mis.map(|e| fold_meta_item(*e)))
                 }
-                MetaNameValue(ref id, s) => MetaNameValue((*id).clone(), s)
+                MetaNameValue(ref id, ref s) => {
+                    MetaNameValue((*id).clone(), (*s).clone())
+                }
             },
         span: fld.new_span(mi.span) }
 }
diff --git a/src/libsyntax/parse/attr.rs b/src/libsyntax/parse/attr.rs
index bc9f7e4b195..c9bea78d02d 100644
--- a/src/libsyntax/parse/attr.rs
+++ b/src/libsyntax/parse/attr.rs
@@ -45,7 +45,7 @@ impl ParserAttr for Parser {
               }
               token::DOC_COMMENT(s) => {
                 let attr = ::attr::mk_sugared_doc_attr(
-                    self.id_to_str(s),
+                    self.id_to_interned_str(s),
                     self.span.lo,
                     self.span.hi
                 );
@@ -133,7 +133,7 @@ impl ParserAttr for Parser {
                 }
                 token::DOC_COMMENT(s) => {
                     self.bump();
-                    ::attr::mk_sugared_doc_attr(self.id_to_str(s),
+                    ::attr::mk_sugared_doc_attr(self.id_to_interned_str(s),
                                                 self.span.lo,
                                                 self.span.hi)
                 }
diff --git a/src/libsyntax/parse/comments.rs b/src/libsyntax/parse/comments.rs
index aa5e4e01ae0..21a34ab5e1e 100644
--- a/src/libsyntax/parse/comments.rs
+++ b/src/libsyntax/parse/comments.rs
@@ -54,7 +54,6 @@ pub fn doc_comment_style(comment: &str) -> ast::AttrStyle {
 }
 
 pub fn strip_doc_comment_decoration(comment: &str) -> ~str {
-
     /// remove whitespace-only lines from the start/end of lines
     fn vertical_trim(lines: ~[~str]) -> ~[~str] {
         let mut i = 0u;
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 93264f5a6c6..636dc504ff2 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -345,7 +345,7 @@ pub struct Parser {
     /// extra detail when the same error is seen twice
     obsolete_set: HashSet<ObsoleteSyntax>,
     /// Used to determine the path to externally loaded source files
-    mod_path_stack: ~[@str],
+    mod_path_stack: ~[InternedString],
     /// Stack of spans of open delimiters. Used for error message.
     open_braces: ~[Span],
     /* do not copy the parser; its state is tied to outside state */
@@ -1408,8 +1408,12 @@ impl Parser {
             token::LIT_FLOAT(s, ft) => LitFloat(self.id_to_str(s), ft),
             token::LIT_FLOAT_UNSUFFIXED(s) =>
                 LitFloatUnsuffixed(self.id_to_str(s)),
-            token::LIT_STR(s) => LitStr(self.id_to_str(s), ast::CookedStr),
-            token::LIT_STR_RAW(s, n) => LitStr(self.id_to_str(s), ast::RawStr(n)),
+            token::LIT_STR(s) => {
+                LitStr(self.id_to_interned_str(s), ast::CookedStr)
+            }
+            token::LIT_STR_RAW(s, n) => {
+                LitStr(self.id_to_interned_str(s), ast::RawStr(n))
+            }
             token::LPAREN => { self.expect(&token::RPAREN); LitNil },
             _ => { self.unexpected_last(tok); }
         }
@@ -4146,11 +4150,11 @@ impl Parser {
     }
 
     fn push_mod_path(&mut self, id: Ident, attrs: &[Attribute]) {
-        let default_path = token::interner_get(id.name);
+        let default_path = self.id_to_interned_str(id);
         let file_path = match ::attr::first_attr_value_str_by_name(attrs,
                                                                    "path") {
             Some(d) => d,
-            None => default_path
+            None => default_path,
         };
         self.mod_path_stack.push(file_path)
     }
diff --git a/src/libsyntax/parse/token.rs b/src/libsyntax/parse/token.rs
index 97b9b4d53a4..9291cba54f6 100644
--- a/src/libsyntax/parse/token.rs
+++ b/src/libsyntax/parse/token.rs
@@ -20,6 +20,7 @@ use std::cast;
 use std::char;
 use std::fmt;
 use std::local_data;
+use std::path::BytesContainer;
 
 #[allow(non_camel_case_types)]
 #[deriving(Clone, Encodable, Decodable, Eq, IterBytes)]
@@ -537,7 +538,7 @@ pub fn get_ident_interner() -> @IdentInterner {
 /// be fixed in the future by just leaking all strings until task death
 /// somehow.
 #[no_send]
-#[deriving(Clone, Eq, IterBytes, TotalEq, TotalOrd)]
+#[deriving(Clone, Eq, IterBytes, Ord, TotalEq, TotalOrd)]
 pub struct InternedString {
     priv string: @str,
 }
@@ -571,6 +572,17 @@ impl InternedString {
     }
 }
 
+impl BytesContainer for InternedString {
+    fn container_as_bytes<'a>(&'a self) -> &'a [u8] {
+        // XXX(pcwalton): This is a workaround for the incorrect signature of
+        // `BytesContainer`, which is itself a workaround for the lack of DST.
+        unsafe {
+            let this = self.get();
+            cast::transmute(this.container_as_bytes())
+        }
+    }
+}
+
 impl fmt::Default for InternedString {
     fn fmt(obj: &InternedString, f: &mut fmt::Formatter) {
         write!(f.buf, "{}", obj.string);
diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index 89d8173f7e7..32b0766249e 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -897,7 +897,7 @@ pub fn print_attribute(s: &mut State, attr: &ast::Attribute) {
     maybe_print_comment(s, attr.span.lo);
     if attr.node.is_sugared_doc {
         let comment = attr.value_str().unwrap();
-        word(&mut s.s, comment);
+        word(&mut s.s, comment.get());
     } else {
         word(&mut s.s, "#[");
         print_meta_item(s, attr.meta());
@@ -1931,10 +1931,10 @@ pub fn print_meta_item(s: &mut State, item: &ast::MetaItem) {
     ibox(s, indent_unit);
     match item.node {
       ast::MetaWord(ref name) => word(&mut s.s, name.get()),
-      ast::MetaNameValue(ref name, value) => {
+      ast::MetaNameValue(ref name, ref value) => {
         word_space(s, name.get());
         word_space(s, "=");
-        print_literal(s, &value);
+        print_literal(s, value);
       }
       ast::MetaList(ref name, ref items) => {
         word(&mut s.s, name.get());
@@ -2172,7 +2172,7 @@ pub fn print_literal(s: &mut State, lit: &ast::Lit) {
       _ => ()
     }
     match lit.node {
-      ast::LitStr(st, style) => print_string(s, st, style),
+      ast::LitStr(ref st, style) => print_string(s, st.get(), style),
       ast::LitChar(ch) => {
           let mut res = ~"'";
           char::from_u32(ch).unwrap().escape_default(|c| res.push_char(c));