From 5f57a508af9c43adc03a4edd575ceae41cc8cd3a Mon Sep 17 00:00:00 2001
From: Brian Anderson <banderson@mozilla.com>
Date: Sat, 27 Aug 2011 18:01:52 -0700
Subject: [PATCH] Convert misc compiler bits to istrs. Issue #855

---
 src/comp/driver/rustc.rs        | 16 ++++-----
 src/comp/front/attr.rs          |  5 +--
 src/comp/metadata/decoder.rs    |  2 +-
 src/comp/metadata/encoder.rs    |  4 +--
 src/comp/middle/kind.rs         | 29 ++++++++--------
 src/comp/middle/trans_alt.rs    |  8 ++---
 src/comp/middle/ty.rs           | 20 +++++------
 src/comp/middle/typeck.rs       |  4 +--
 src/comp/syntax/ext/env.rs      |  8 ++---
 src/comp/syntax/ext/fmt.rs      | 61 +++++++++++++++++----------------
 src/comp/syntax/ext/simplext.rs | 25 +++++++-------
 src/comp/util/ppaux.rs          |  2 +-
 12 files changed, 93 insertions(+), 91 deletions(-)

diff --git a/src/comp/driver/rustc.rs b/src/comp/driver/rustc.rs
index 9bb5750aab2b..fffdcc75bf30 100644
--- a/src/comp/driver/rustc.rs
+++ b/src/comp/driver/rustc.rs
@@ -47,21 +47,21 @@ fn default_configuration(sess: session::session,
    ast::crate_cfg {
     let libc =
         alt sess.get_targ_cfg().os {
-          session::os_win32. { "msvcrt.dll" }
-          session::os_macos. { "libc.dylib" }
-          session::os_linux. { "libc.so.6" }
-          _ { "libc.so" }
+          session::os_win32. { ~"msvcrt.dll" }
+          session::os_macos. { ~"libc.dylib" }
+          session::os_linux. { ~"libc.so.6" }
+          _ { ~"libc.so" }
         };
 
     let mk = attr::mk_name_value_item_str;
 
     ret [ // Target bindings.
-         mk(~"target_os", istr::to_estr(std::os::target_os())),
-        mk(~"target_arch", "x86"),
+         mk(~"target_os", std::os::target_os()),
+        mk(~"target_arch", ~"x86"),
          mk(~"target_libc", libc),
          // Build bindings.
-         mk(~"build_compiler", istr::to_estr(argv0)),
-        mk(~"build_input", istr::to_estr(input))];
+         mk(~"build_compiler", argv0),
+        mk(~"build_input", input)];
 }
 
 fn build_configuration(sess: session::session, argv0: &istr, input: &istr) ->
diff --git a/src/comp/front/attr.rs b/src/comp/front/attr.rs
index 516da981af3f..0d85a083554e 100644
--- a/src/comp/front/attr.rs
+++ b/src/comp/front/attr.rs
@@ -197,8 +197,9 @@ fn span<@T>(item: &T) -> ast::spanned<T> {
     ret {node: item, span: ast_util::dummy_sp()};
 }
 
-fn mk_name_value_item_str(name: ast::ident, value: str) -> @ast::meta_item {
-    let value_lit = span(ast::lit_str(istr::from_estr(value), ast::sk_rc));
+fn mk_name_value_item_str(name: ast::ident,
+                          value: &istr) -> @ast::meta_item {
+    let value_lit = span(ast::lit_str(value, ast::sk_rc));
     ret mk_name_value_item(name, value_lit);
 }
 
diff --git a/src/comp/metadata/decoder.rs b/src/comp/metadata/decoder.rs
index a1ab2a521c4b..92247cb55a84 100644
--- a/src/comp/metadata/decoder.rs
+++ b/src/comp/metadata/decoder.rs
@@ -310,7 +310,7 @@ fn get_meta_items(md: &ebml::doc) -> [@ast::meta_item] {
         let nd = ebml::get_doc(meta_item_doc, tag_meta_item_name);
         let vd = ebml::get_doc(meta_item_doc, tag_meta_item_value);
         let n = istr::unsafe_from_bytes(ebml::doc_data(nd));
-        let v = str::unsafe_from_bytes(ebml::doc_data(vd));
+        let v = istr::unsafe_from_bytes(ebml::doc_data(vd));
         // FIXME (#611): Should be able to decode meta_name_value variants,
         // but currently they can't be encoded
         items += [attr::mk_name_value_item_str(n, v)];
diff --git a/src/comp/metadata/encoder.rs b/src/comp/metadata/encoder.rs
index c5dd0fa4cefb..269a49acbe6a 100644
--- a/src/comp/metadata/encoder.rs
+++ b/src/comp/metadata/encoder.rs
@@ -511,10 +511,10 @@ fn synthesize_crate_attrs(ecx: &@encode_ctxt, crate: &@crate) -> [attribute] {
 
         let name_item =
             attr::mk_name_value_item_str(
-                ~"name", istr::to_estr(ecx.ccx.link_meta.name));
+                ~"name", ecx.ccx.link_meta.name);
         let vers_item =
             attr::mk_name_value_item_str(
-                ~"vers", istr::to_estr(ecx.ccx.link_meta.vers));
+                ~"vers", ecx.ccx.link_meta.vers);
 
         let other_items =
             {
diff --git a/src/comp/middle/kind.rs b/src/comp/middle/kind.rs
index 3846620103c4..74cc3b4cada5 100644
--- a/src/comp/middle/kind.rs
+++ b/src/comp/middle/kind.rs
@@ -112,44 +112,45 @@ fn type_and_kind(tcx: &ty::ctxt, e: &@ast::expr) ->
 }
 
 fn need_expr_kind(tcx: &ty::ctxt, e: &@ast::expr, k_need: ast::kind,
-                  descr: &str) {
+                  descr: &istr) {
     let tk = type_and_kind(tcx, e);
-    log #fmt["for %s: want %s type, got %s type %s", descr,
+    log #fmt["for %s: want %s type, got %s type %s", istr::to_estr(descr),
              kind_to_str(k_need), kind_to_str(tk.kind),
              istr::to_estr(util::ppaux::ty_to_str(tcx, tk.ty))];
 
     if !kind_lteq(k_need, tk.kind) {
         let s =
             #fmt["mismatched kinds for %s: needed %s type, got %s type %s",
-                 descr, kind_to_str(k_need), kind_to_str(tk.kind),
+                 istr::to_estr(descr), kind_to_str(k_need),
+                 kind_to_str(tk.kind),
                  istr::to_estr(util::ppaux::ty_to_str(tcx, tk.ty))];
         tcx.sess.span_err(e.span, istr::from_estr(s));
     }
 }
 
 fn need_shared_lhs_rhs(tcx: &ty::ctxt, a: &@ast::expr, b: &@ast::expr,
-                       op: &str) {
-    need_expr_kind(tcx, a, ast::kind_shared, op + " lhs");
-    need_expr_kind(tcx, b, ast::kind_shared, op + " rhs");
+                       op: &istr) {
+    need_expr_kind(tcx, a, ast::kind_shared, op + ~" lhs");
+    need_expr_kind(tcx, b, ast::kind_shared, op + ~" rhs");
 }
 
 fn check_expr(tcx: &ty::ctxt, e: &@ast::expr) {
     alt e.node {
-      ast::expr_move(a, b) { need_shared_lhs_rhs(tcx, a, b, "<-"); }
-      ast::expr_assign(a, b) { need_shared_lhs_rhs(tcx, a, b, "="); }
-      ast::expr_assign_op(_, a, b) { need_shared_lhs_rhs(tcx, a, b, "op="); }
-      ast::expr_swap(a, b) { need_shared_lhs_rhs(tcx, a, b, "<->"); }
+      ast::expr_move(a, b) { need_shared_lhs_rhs(tcx, a, b, ~"<-"); }
+      ast::expr_assign(a, b) { need_shared_lhs_rhs(tcx, a, b, ~"="); }
+      ast::expr_assign_op(_, a, b) { need_shared_lhs_rhs(tcx, a, b, ~"op="); }
+      ast::expr_swap(a, b) { need_shared_lhs_rhs(tcx, a, b, ~"<->"); }
       ast::expr_copy(a) {
-        need_expr_kind(tcx, a, ast::kind_shared, "'copy' operand");
+        need_expr_kind(tcx, a, ast::kind_shared, ~"'copy' operand");
       }
       ast::expr_ret(option::some(a)) {
-        need_expr_kind(tcx, a, ast::kind_shared, "'ret' operand");
+        need_expr_kind(tcx, a, ast::kind_shared, ~"'ret' operand");
       }
       ast::expr_be(a) {
-        need_expr_kind(tcx, a, ast::kind_shared, "'be' operand");
+        need_expr_kind(tcx, a, ast::kind_shared, ~"'be' operand");
       }
       ast::expr_fail(option::some(a)) {
-        need_expr_kind(tcx, a, ast::kind_shared, "'fail' operand");
+        need_expr_kind(tcx, a, ast::kind_shared, ~"'fail' operand");
       }
       ast::expr_call(callee, _) {
         let tpt = ty::expr_ty_params_and_ty(tcx, callee);
diff --git a/src/comp/middle/trans_alt.rs b/src/comp/middle/trans_alt.rs
index 4491fca0e200..53193ad98beb 100644
--- a/src/comp/middle/trans_alt.rs
+++ b/src/comp/middle/trans_alt.rs
@@ -58,9 +58,9 @@ fn variant_opt(ccx: &@crate_ctxt, pat_id: ast::node_id) -> opt {
 }
 
 type bind_map = [{ident: ast::ident, val: ValueRef}];
-fn assoc(key: str, list: &bind_map) -> option::t<ValueRef> {
+fn assoc(key: &istr, list: &bind_map) -> option::t<ValueRef> {
     for elt: {ident: ast::ident, val: ValueRef} in list {
-        if istr::eq(elt.ident, istr::from_estr(key)) { ret some(elt.val); }
+        if istr::eq(elt.ident, key) { ret some(elt.val); }
     }
     ret none;
 }
@@ -304,7 +304,7 @@ fn compile_submatch(bcx: @block_ctxt, m: &match, vals: [ValueRef],
             // the actual arm block.
             for each @{key, val} in data.id_map.items() {
                 bcx.fcx.lllocals.insert
-                    (val, option::get(assoc(istr::to_estr(key),
+                    (val, option::get(assoc(key,
                                             m[0].bound)));
             }
             let {bcx: guard_bcx, val: guard_val} =
@@ -474,7 +474,7 @@ fn make_phi_bindings(bcx: &@block_ctxt, map: &[exit_node],
         let vals = [];
         for ex: exit_node in map {
             if ex.to as uint == our_block {
-                alt assoc(istr::to_estr(item.key), ex.bound) {
+                alt assoc(item.key, ex.bound) {
                   some(val) { llbbs += [ex.from]; vals += [val]; }
                   none. { }
                 }
diff --git a/src/comp/middle/ty.rs b/src/comp/middle/ty.rs
index 67f5b62a12ea..eec50b5f454c 100644
--- a/src/comp/middle/ty.rs
+++ b/src/comp/middle/ty.rs
@@ -243,7 +243,7 @@ fn method_ty_to_fn_ty(cx: &ctxt, m: method) -> t {
 // Never construct these manually. These are interned.
 type raw_t =
     {struct: sty,
-     cname: option::t<str>,
+     cname: option::t<istr>,
      hash: uint,
      has_params: bool,
      has_vars: bool};
@@ -427,8 +427,8 @@ fn mk_ctxt(s: session::session, dm: resolve::def_map,
 
 
 // Type constructors
-fn mk_raw_ty(cx: &ctxt, st: &sty, _in_cname: &option::t<str>) -> @raw_t {
-    let cname = none;
+fn mk_raw_ty(cx: &ctxt, st: &sty, _in_cname: &option::t<istr>) -> @raw_t {
+    let cname: option::t<istr> = none;
     let h = hash_type_info(st, cname);
     let has_params: bool = false;
     let has_vars: bool = false;
@@ -505,11 +505,11 @@ fn mk_raw_ty(cx: &ctxt, st: &sty, _in_cname: &option::t<str>) -> @raw_t {
           has_vars: has_vars};
 }
 
-fn intern(cx: &ctxt, st: &sty, cname: &option::t<str>) {
+fn intern(cx: &ctxt, st: &sty, cname: &option::t<istr>) {
     interner::intern(*cx.ts, mk_raw_ty(cx, st, cname));
 }
 
-fn gen_ty_full(cx: &ctxt, st: &sty, cname: &option::t<str>) -> t {
+fn gen_ty_full(cx: &ctxt, st: &sty, cname: &option::t<istr>) -> t {
     let raw_type = mk_raw_ty(cx, st, cname);
     ret interner::intern(*cx.ts, raw_type);
 }
@@ -617,7 +617,7 @@ fn struct(cx: &ctxt, typ: t) -> sty {
 
 
 // Returns the canonical name of the given type.
-fn cname(cx: &ctxt, typ: t) -> option::t<str> {
+fn cname(cx: &ctxt, typ: t) -> option::t<istr> {
     ret interner::get(*cx.ts, typ).cname;
 }
 
@@ -794,7 +794,7 @@ fn fold_ty(cx: &ctxt, fld: fold_mode, ty_0: t) -> t {
 
 // Type utilities
 
-fn rename(cx: &ctxt, typ: t, new_cname: str) -> t {
+fn rename(cx: &ctxt, typ: t, new_cname: &istr) -> t {
     ret gen_ty_full(cx, struct(cx, typ), some(new_cname));
 }
 
@@ -1538,11 +1538,11 @@ fn hash_type_structure(st: &sty) -> uint {
     }
 }
 
-fn hash_type_info(st: &sty, cname_opt: &option::t<str>) -> uint {
+fn hash_type_info(st: &sty, cname_opt: &option::t<istr>) -> uint {
     let h = hash_type_structure(st);
     alt cname_opt {
       none. {/* no-op */ }
-      some(s) { h += h << 5u + str::hash(s); }
+      some(s) { h += h << 5u + istr::hash(s); }
     }
     ret h;
 }
@@ -1606,7 +1606,7 @@ fn eq_raw_ty(a: &@raw_t, b: &@raw_t) -> bool {
       none. { alt b.cname { none. {/* ok */ } _ { ret false; } } }
       some(s_a) {
         alt b.cname {
-          some(s_b) { if !str::eq(s_a, s_b) { ret false; } }
+          some(s_b) { if !istr::eq(s_a, s_b) { ret false; } }
           _ { ret false; }
         }
       }
diff --git a/src/comp/middle/typeck.rs b/src/comp/middle/typeck.rs
index 446d56182f02..57baf194938d 100644
--- a/src/comp/middle/typeck.rs
+++ b/src/comp/middle/typeck.rs
@@ -417,7 +417,7 @@ fn ast_ty_to_ty(tcx: &ty::ctxt, getter: &ty_getter, ast_ty: &@ast::ty) ->
     alt cname {
       none. {/* no-op */ }
       some(cname_str) {
-        typ = ty::rename(tcx, typ, istr::to_estr(cname_str));
+        typ = ty::rename(tcx, typ, cname_str);
       }
     }
     tcx.ast_ty_to_ty_cache.insert(ast_ty, some(typ));
@@ -629,7 +629,7 @@ mod collect {
                  ty_params: &[ast::ty_param]) -> ty::ty_param_kinds_and_ty {
         let methods = get_obj_method_types(cx, ob);
         let t_obj = ty::mk_obj(cx.tcx, ty::sort_methods(methods));
-        t_obj = ty::rename(cx.tcx, t_obj, istr::to_estr(id));
+        t_obj = ty::rename(cx.tcx, t_obj, id);
         ret {kinds: ty_param_kinds(ty_params), ty: t_obj};
     }
     fn ty_of_obj_ctor(cx: @ctxt, id: &ast::ident, ob: &ast::_obj,
diff --git a/src/comp/syntax/ext/env.rs b/src/comp/syntax/ext/env.rs
index a183e8f34553..23feb43d817d 100644
--- a/src/comp/syntax/ext/env.rs
+++ b/src/comp/syntax/ext/env.rs
@@ -28,15 +28,15 @@ fn expand_syntax_ext(cx: &ext_ctxt, sp: codemap::span, arg: @ast::expr,
 
     let var = expr_to_str(cx, args[0], ~"#env requires a string");
     alt generic_os::getenv(var) {
-      option::none. { ret make_new_str(cx, sp, ""); }
+      option::none. { ret make_new_str(cx, sp, ~""); }
       option::some(s) {
-        ret make_new_str(cx, sp, istr::to_estr(s));
+        ret make_new_str(cx, sp, s);
       }
     }
 }
 
-fn make_new_str(cx: &ext_ctxt, sp: codemap::span, s: str) -> @ast::expr {
-    ret make_new_lit(cx, sp, ast::lit_str(istr::from_estr(s), ast::sk_rc));
+fn make_new_str(cx: &ext_ctxt, sp: codemap::span, s: &istr) -> @ast::expr {
+    ret make_new_lit(cx, sp, ast::lit_str(s, ast::sk_rc));
 }
 //
 // Local Variables:
diff --git a/src/comp/syntax/ext/fmt.rs b/src/comp/syntax/ext/fmt.rs
index 1bdd819d7086..121300f64902 100644
--- a/src/comp/syntax/ext/fmt.rs
+++ b/src/comp/syntax/ext/fmt.rs
@@ -52,8 +52,8 @@ fn pieces_to_expr(cx: &ext_ctxt, sp: span, pieces: &[piece],
         let sp_lit = @{node: lit, span: sp};
         ret @{id: cx.next_id(), node: ast::expr_lit(sp_lit), span: sp};
     }
-    fn make_new_str(cx: &ext_ctxt, sp: span, s: str) -> @ast::expr {
-        let lit = ast::lit_str(istr::from_estr(s), ast::sk_rc);
+    fn make_new_str(cx: &ext_ctxt, sp: span, s: &istr) -> @ast::expr {
+        let lit = ast::lit_str(s, ast::sk_rc);
         ret make_new_lit(cx, sp, lit);
     }
     fn make_new_int(cx: &ext_ctxt, sp: span, i: int) -> @ast::expr {
@@ -109,8 +109,9 @@ fn pieces_to_expr(cx: &ext_ctxt, sp: span, pieces: &[piece],
             ret [~"extfmt", ~"rt", ident];
         } else { ret [~"std", ~"extfmt", ~"rt", ident]; }
     }
-    fn make_rt_path_expr(cx: &ext_ctxt, sp: span, ident: str) -> @ast::expr {
-        let path = make_path_vec(cx, istr::from_estr(ident));
+    fn make_rt_path_expr(cx: &ext_ctxt, sp: span,
+                         ident: &istr) -> @ast::expr {
+        let path = make_path_vec(cx, ident);
         ret make_path_expr(cx, sp, path);
     }
     // Produces an AST expression that represents a RT::conv record,
@@ -122,11 +123,11 @@ fn pieces_to_expr(cx: &ext_ctxt, sp: span, pieces: &[piece],
             for f: flag in flags {
                 let fstr;
                 alt f {
-                  flag_left_justify. { fstr = "flag_left_justify"; }
-                  flag_left_zero_pad. { fstr = "flag_left_zero_pad"; }
-                  flag_space_for_sign. { fstr = "flag_space_for_sign"; }
-                  flag_sign_always. { fstr = "flag_sign_always"; }
-                  flag_alternate. { fstr = "flag_alternate"; }
+                  flag_left_justify. { fstr = ~"flag_left_justify"; }
+                  flag_left_zero_pad. { fstr = ~"flag_left_zero_pad"; }
+                  flag_space_for_sign. { fstr = ~"flag_space_for_sign"; }
+                  flag_sign_always. { fstr = ~"flag_sign_always"; }
+                  flag_alternate. { fstr = ~"flag_alternate"; }
                 }
                 flagexprs += [make_rt_path_expr(cx, sp, fstr)];
             }
@@ -135,14 +136,14 @@ fn pieces_to_expr(cx: &ext_ctxt, sp: span, pieces: &[piece],
             // this is a hack placeholder flag
 
             if vec::len::<@ast::expr>(flagexprs) == 0u {
-                flagexprs += [make_rt_path_expr(cx, sp, "flag_none")];
+                flagexprs += [make_rt_path_expr(cx, sp, ~"flag_none")];
             }
             ret make_vec_expr(cx, sp, flagexprs);
         }
         fn make_count(cx: &ext_ctxt, sp: span, cnt: &count) -> @ast::expr {
             alt cnt {
               count_implied. {
-                ret make_rt_path_expr(cx, sp, "count_implied");
+                ret make_rt_path_expr(cx, sp, ~"count_implied");
               }
               count_is(c) {
                 let count_lit = make_new_int(cx, sp, c);
@@ -158,13 +159,13 @@ fn pieces_to_expr(cx: &ext_ctxt, sp: span, pieces: &[piece],
             alt t {
               ty_hex(c) {
                 alt c {
-                  case_upper. { rt_type = "ty_hex_upper"; }
-                  case_lower. { rt_type = "ty_hex_lower"; }
+                  case_upper. { rt_type = ~"ty_hex_upper"; }
+                  case_lower. { rt_type = ~"ty_hex_lower"; }
                 }
               }
-              ty_bits. { rt_type = "ty_bits"; }
-              ty_octal. { rt_type = "ty_octal"; }
-              _ { rt_type = "ty_default"; }
+              ty_bits. { rt_type = ~"ty_bits"; }
+              ty_octal. { rt_type = ~"ty_octal"; }
+              _ { rt_type = ~"ty_default"; }
             }
             ret make_rt_path_expr(cx, sp, rt_type);
         }
@@ -184,9 +185,9 @@ fn pieces_to_expr(cx: &ext_ctxt, sp: span, pieces: &[piece],
         ret make_conv_rec(cx, sp, rt_conv_flags, rt_conv_width,
                           rt_conv_precision, rt_conv_ty);
     }
-    fn make_conv_call(cx: &ext_ctxt, sp: span, conv_type: str, cnv: &conv,
-                      arg: @ast::expr) -> @ast::expr {
-        let fname = ~"conv_" + istr::from_estr(conv_type);
+    fn make_conv_call(cx: &ext_ctxt, sp: span, conv_type: &istr,
+                      cnv: &conv, arg: @ast::expr) -> @ast::expr {
+        let fname = ~"conv_" + conv_type;
         let path = make_path_vec(cx, fname);
         let cnv_expr = make_rt_conv_expr(cx, sp, cnv);
         let args = [cnv_expr, arg];
@@ -241,21 +242,21 @@ fn pieces_to_expr(cx: &ext_ctxt, sp: span, pieces: &[piece],
           _ { cx.span_unimpl(sp, unsupported); }
         }
         alt cnv.ty {
-          ty_str. { ret make_conv_call(cx, arg.span, "str", cnv, arg); }
-          ty_istr. { ret make_conv_call(cx, arg.span, "istr", cnv, arg); }
+          ty_str. { ret make_conv_call(cx, arg.span, ~"str", cnv, arg); }
+          ty_istr. { ret make_conv_call(cx, arg.span, ~"istr", cnv, arg); }
           ty_int(sign) {
             alt sign {
-              signed. { ret make_conv_call(cx, arg.span, "int", cnv, arg); }
+              signed. { ret make_conv_call(cx, arg.span, ~"int", cnv, arg); }
               unsigned. {
-                ret make_conv_call(cx, arg.span, "uint", cnv, arg);
+                ret make_conv_call(cx, arg.span, ~"uint", cnv, arg);
               }
             }
           }
-          ty_bool. { ret make_conv_call(cx, arg.span, "bool", cnv, arg); }
-          ty_char. { ret make_conv_call(cx, arg.span, "char", cnv, arg); }
-          ty_hex(_) { ret make_conv_call(cx, arg.span, "uint", cnv, arg); }
-          ty_bits. { ret make_conv_call(cx, arg.span, "uint", cnv, arg); }
-          ty_octal. { ret make_conv_call(cx, arg.span, "uint", cnv, arg); }
+          ty_bool. { ret make_conv_call(cx, arg.span, ~"bool", cnv, arg); }
+          ty_char. { ret make_conv_call(cx, arg.span, ~"char", cnv, arg); }
+          ty_hex(_) { ret make_conv_call(cx, arg.span, ~"uint", cnv, arg); }
+          ty_bits. { ret make_conv_call(cx, arg.span, ~"uint", cnv, arg); }
+          ty_octal. { ret make_conv_call(cx, arg.span, ~"uint", cnv, arg); }
           _ { cx.span_unimpl(sp, unsupported); }
         }
     }
@@ -319,12 +320,12 @@ fn pieces_to_expr(cx: &ext_ctxt, sp: span, pieces: &[piece],
     }
     let fmt_sp = args[0].span;
     let n = 0u;
-    let tmp_expr = make_new_str(cx, sp, "");
+    let tmp_expr = make_new_str(cx, sp, ~"");
     let nargs = vec::len::<@ast::expr>(args);
     for pc: piece in pieces {
         alt pc {
           piece_string(s) {
-            let s_expr = make_new_str(cx, fmt_sp, s);
+            let s_expr = make_new_str(cx, fmt_sp, istr::from_estr(s));
             tmp_expr = make_add_expr(cx, fmt_sp, tmp_expr, s_expr);
           }
           piece_conv(conv) {
diff --git a/src/comp/syntax/ext/simplext.rs b/src/comp/syntax/ext/simplext.rs
index 247b5aee150f..ccd792d78f57 100644
--- a/src/comp/syntax/ext/simplext.rs
+++ b/src/comp/syntax/ext/simplext.rs
@@ -57,8 +57,7 @@ tag matchable {
 }
 
 /* for when given an incompatible bit of AST */
-fn match_error(cx: &ext_ctxt, m: &matchable, expected: &str) -> ! {
-    let expected = istr::from_estr(expected);
+fn match_error(cx: &ext_ctxt, m: &matchable, expected: &istr) -> ! {
     alt m {
       match_expr(x) {
         cx.span_fatal(x.span,
@@ -355,7 +354,7 @@ fn transcribe_ident(cx: &ext_ctxt, b: &bindings, idx_path: @mutable [uint],
                     i: &ident, _fld: ast_fold) -> ident {
     ret alt follow_for_trans(cx, b.find(i), idx_path) {
           some(match_ident(a_id)) { a_id.node }
-          some(m) { match_error(cx, m, "an identifier") }
+          some(m) { match_error(cx, m, ~"an identifier") }
           none. { i }
         }
 }
@@ -370,7 +369,7 @@ fn transcribe_path(cx: &ext_ctxt, b: &bindings, idx_path: @mutable [uint],
             {global: false, idents: [id.node], types: []}
           }
           some(match_path(a_pth)) { a_pth.node }
-          some(m) { match_error(cx, m, "a path") }
+          some(m) { match_error(cx, m, ~"a path") }
           none. { p }
         }
 }
@@ -395,7 +394,7 @@ fn transcribe_expr(cx: &ext_ctxt, b: &bindings, idx_path: @mutable [uint],
               }
               some(match_path(a_pth)) { expr_path(a_pth) }
               some(match_expr(a_exp)) { a_exp.node }
-              some(m) { match_error(cx, m, "an expression") }
+              some(m) { match_error(cx, m, ~"an expression") }
               none. { orig(e, fld) }
             }
           }
@@ -412,7 +411,7 @@ fn transcribe_type(cx: &ext_ctxt, b: &bindings, idx_path: @mutable [uint],
               some(id) {
                 alt follow_for_trans(cx, b.find(id), idx_path) {
                   some(match_ty(ty)) { ty.node }
-                  some(m) { match_error(cx, m, "a type") }
+                  some(m) { match_error(cx, m, ~"a type") }
                   none. { orig(t, fld) }
                 }
               }
@@ -439,7 +438,7 @@ fn transcribe_block(cx: &ext_ctxt, b: &bindings, idx_path: @mutable [uint],
 
               // possibly allow promotion of ident/path/expr to blocks?
               some(m) {
-                match_error(cx, m, "a block")
+                match_error(cx, m, ~"a block")
               }
               none. { orig(blk, fld) }
             }
@@ -564,13 +563,13 @@ fn p_t_s_r_mac(cx: &ext_ctxt, mac: &ast::mac, s: &selector, b: &binders) {
               _ { cx.bug(~"broken traversal in p_t_s_r") }
             }
     }
-    fn no_des(cx: &ext_ctxt, sp: &span, syn: &str) -> ! {
+    fn no_des(cx: &ext_ctxt, sp: &span, syn: &istr) -> ! {
         cx.span_fatal(sp, ~"destructuring "
-                      + istr::from_estr(syn) + ~" is not yet supported");
+                      + syn + ~" is not yet supported");
     }
     alt mac.node {
       ast::mac_ellipsis. { cx.span_fatal(mac.span, ~"misused `...`"); }
-      ast::mac_invoc(_, _, _) { no_des(cx, mac.span, "macro calls"); }
+      ast::mac_invoc(_, _, _) { no_des(cx, mac.span, ~"macro calls"); }
       ast::mac_embed_type(ty) {
         alt ty.node {
           ast::ty_path(pth, _) {
@@ -587,10 +586,10 @@ fn p_t_s_r_mac(cx: &ext_ctxt, mac: &ast::mac, s: &selector, b: &binders) {
                 b.real_binders.insert(
                     id, compose_sels(s, final_step));
               }
-              none. { no_des(cx, pth.span, "under `#<>`"); }
+              none. { no_des(cx, pth.span, ~"under `#<>`"); }
             }
           }
-          _ { no_des(cx, ty.span, "under `#<>`"); }
+          _ { no_des(cx, ty.span, ~"under `#<>`"); }
         }
       }
       ast::mac_embed_block(blk) {
@@ -608,7 +607,7 @@ fn p_t_s_r_mac(cx: &ext_ctxt, mac: &ast::mac, s: &selector, b: &binders) {
             b.real_binders.insert(id,
                                   compose_sels(s, final_step));
           }
-          none. { no_des(cx, blk.span, "under `#{}`"); }
+          none. { no_des(cx, blk.span, ~"under `#{}`"); }
         }
       }
     }
diff --git a/src/comp/util/ppaux.rs b/src/comp/util/ppaux.rs
index 4ef7cfc60a88..667a0f27fb8b 100644
--- a/src/comp/util/ppaux.rs
+++ b/src/comp/util/ppaux.rs
@@ -102,7 +102,7 @@ fn ty_to_str(cx: &ctxt, typ: &t) -> istr {
     }
     alt cname(cx, typ) {
       some(cs) {
-        ret istr::from_estr(cs);
+        ret cs;
       }
       _ { }
     }