Switch to using Boost.Format

36 files changed, 245 insertions, 440 deletions

diff --git a/src/accum.cc b/src/accum.cc
deleted file mode 100644
index 3add051b..00000000
--- a/src/accum.cc
+++ /dev/null
@@ -1,77 +0,0 @@
-/*
- * Copyright (c) 2003-2012, John Wiegley.  All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
- *
- * - Redistributions of source code must retain the above copyright
- *   notice, this list of conditions and the following disclaimer.
- *
- * - Redistributions in binary form must reproduce the above copyright
- *   notice, this list of conditions and the following disclaimer in the
- *   documentation and/or other materials provided with the distribution.
- *
- * - Neither the name of New Artisans LLC nor the names of its
- *   contributors may be used to endorse or promote products derived from
- *   this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <system.hh>
-
-#include "utils.h"
-
-namespace ledger {
-
-straccstream       _accum;
-std::ostringstream _accum_buffer;
-
-std::streamsize straccbuf::xsputn(const char * s, std::streamsize num)
-{
-  if (index == 0) {
-    // The first item received is the format string
-    str = std::string(s, static_cast<std::string::size_type>(num));
-  }
-  else {
-    std::ostringstream buf;
-
-    // Every item thereafter is an argument that substitutes for %# in the
-    // format string
-    bool matched = false;
-    for (const char * p = str.c_str(); *p; p++) {
-      if (*p == '%') {
-        const char * q = p + 1;
-        if (*q && *q != '%' && std::isdigit(*q) &&
-            std::string::size_type(*q - '0') == index) {
-          p++;
-          buf << std::string(s, static_cast<std::string::size_type>(num));
-          matched = true;
-        } else {
-          buf << *p;
-        }
-      } else {
-        buf << *p;
-      }
-    }
-    if (! matched)
-      buf << std::string(s, static_cast<std::string::size_type>(num));
-
-    str = buf.str();
-  }
-  index++;
-  return num;
-}
-
-} // namespace ledger
diff --git a/src/accum.h b/src/accum.h
deleted file mode 100644
index 628a6b36..00000000
--- a/src/accum.h
+++ /dev/null
@@ -1,111 +0,0 @@
-/*
- * Copyright (c) 2003-2012, John Wiegley.  All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * - Redistributions of source code must retain the above copyright
- *   notice, this list of conditions and the following disclaimer.
- *
- * - Redistributions in binary form must reproduce the above copyright
- *   notice, this list of conditions and the following disclaimer in the
- *   documentation and/or other materials provided with the distribution.
- *
- * - Neither the name of New Artisans LLC nor the names of its
- *   contributors may be used to endorse or promote products derived from
- *   this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-/**
- * @addtogroup util
- */
-
-/**
- * @file   accum.h
- * @author John Wiegley
- *
- * @ingroup util
- */
-#ifndef _ACCUM_H
-#define _ACCUM_H
-
-namespace ledger {
-
-class straccbuf : public std::streambuf
-{
-protected:
-  std::string            str;   // accumulator
-  std::string::size_type index;
-
-public:
-  straccbuf() : index(0) {
-    TRACE_CTOR(straccbuf, "");
-  }
-  ~straccbuf() throw() {
-    TRACE_DTOR(straccbuf);
-  }
-
-protected:
-  virtual std::streamsize xsputn(const char * s, std::streamsize num);
-
-  friend class straccstream;
-};
-
-class straccstream : public std::ostream
-{
-protected:
-  straccbuf buf;
-
-public:
-  straccstream() : std::ostream(0) {
-    TRACE_CTOR(straccstream, "");
-    rdbuf(&buf);
-  }
-  ~straccstream() throw() {
-    TRACE_DTOR(straccstream);
-  }
-
-  void clear() {
-    std::ostream::clear();
-    buf.pubseekoff(0, ios_base::beg);
-    buf.str.clear();
-    buf.index = 0;
-  }
-
-  std::string str() const {
-    return buf.str;
-  }
-};
-
-#define ACCUM(obj) (static_cast<const straccstream&>(obj).str())
-
-extern straccstream       _accum;
-extern std::ostringstream _accum_buffer;
-
-inline string str_helper_func() {
-  string buf = _accum_buffer.str();
-  _accum_buffer.clear();
-  _accum_buffer.str("");
-  return buf;
-}
-
-#define STR(msg)                                \
-  ((_accum_buffer << ACCUM(_accum << msg)),     \
-   _accum.clear(), str_helper_func())
-
-} // namespace ledger
-
-#endif // _ACCUM_H
diff --git a/src/amount.cc b/src/amount.cc
index 5e933215..803787e8 100644
--- a/src/amount.cc
+++ b/src/amount.cc
@@ -397,8 +397,8 @@ int amount_t::compare(const amount_t& amt) const
 
   if (has_commodity() && amt.has_commodity() && commodity() != amt.commodity()) {
     throw_(amount_error,
-           _("Cannot compare amounts with different commodities: '%1' and '%2'")
-           << commodity() << amt.commodity());
+           _f("Cannot compare amounts with different commodities: '%1%' and '%2%'")
+           % commodity() % amt.commodity());
   }
 
   return mpq_cmp(MP(quantity), MP(amt.quantity));
@@ -432,8 +432,8 @@ amount_t& amount_t::operator+=(const amount_t& amt)
 
   if (has_commodity() && amt.has_commodity() && commodity() != amt.commodity()) {
     throw_(amount_error,
-           _("Adding amounts with different commodities: '%1' != '%2'")
-           << commodity() << amt.commodity());
+           _f("Adding amounts with different commodities: '%1%' != '%2%'")
+           % commodity() % amt.commodity());
   }
 
   _dup();
@@ -462,8 +462,8 @@ amount_t& amount_t::operator-=(const amount_t& amt)
 
   if (has_commodity() && amt.has_commodity() && commodity() != amt.commodity()) {
     throw_(amount_error,
-           _("Subtracting amounts with different commodities: '%1' != '%2'")
-           << commodity() << amt.commodity());
+           _f("Subtracting amounts with different commodities: '%1%' != '%2%'")
+           % commodity() % amt.commodity());
   }
 
   _dup();
diff --git a/src/balance.cc b/src/balance.cc
index ded3d38a..42034ff8 100644
--- a/src/balance.cc
+++ b/src/balance.cc
@@ -216,8 +216,8 @@ balance_t::commodity_amount(const optional<const commodity_t&>& commodity) const
         return temp.commodity_amount(commodity);
 
       throw_(amount_error,
-             _("Requested amount of a balance with multiple commodities: %1")
-             << temp);
+             _f("Requested amount of a balance with multiple commodities: %1%")
+             % temp);
     }
   }
   else if (amounts.size() > 0) {
diff --git a/src/context.h b/src/context.h
index 45bb9990..09734b3e 100644
--- a/src/context.h
+++ b/src/context.h
@@ -103,6 +103,9 @@ public:
   void warning(const string& what) const {
     warning_func(location() + what);
   }
+  void warning(const boost::format& what) const {
+    warning_func(location() + string(what.str()));
+  }
 };
 
 inline parse_context_t open_for_reading(const path& pathname,
@@ -112,7 +115,7 @@ inline parse_context_t open_for_reading(const path& pathname,
 
   if (! exists(filename))
     throw_(std::runtime_error,
-           _("Cannot read journal file %1") << filename);
+           _f("Cannot read journal file %1%") % filename);
 
 #if BOOST_VERSION >= 104600 && BOOST_FILESYSTEM_VERSION >= 3
   path parent(filesystem::absolute(pathname, cwd).parent_path());
diff --git a/src/convert.cc b/src/convert.cc
index e8ca241e..f0d8db06 100644
--- a/src/convert.cc
+++ b/src/convert.cc
@@ -119,8 +119,8 @@ value_t convert_command(call_scope_t& args)
     formatter.flush();
   }
   catch (const std::exception&) {
-    add_error_context(_("While parsing file %1")
-                      << file_context(reader.get_pathname(),
+    add_error_context(_f("While parsing file %1%")
+                      % file_context(reader.get_pathname(),
                                       reader.get_linenum()));
     add_error_context(_("While parsing CSV line:"));
     add_error_context(line_context(reader.get_last_line()));
diff --git a/src/draft.cc b/src/draft.cc
index 43c214cb..c5f37f42 100644
--- a/src/draft.cc
+++ b/src/draft.cc
@@ -68,7 +68,7 @@ void draft_t::xact_template_t::dump(std::ostream& out) const
   } else {
     foreach (const post_template_t& post, posts) {
       out << std::endl
-          << STR(_("[Posting \"%1\"]") << (post.from ? _("from") : _("to")))
+          << _f("[Posting \"%1\"]") % (post.from ? _("from") : _("to"))
           << std::endl;
 
       if (post.account_mask)
@@ -307,8 +307,8 @@ xact_t * draft_t::insert(journal_t& journal)
       }
     } else {
       throw_(std::runtime_error,
-             _("No accounts, and no past transaction matching '%1'")
-             << tmpl->payee_mask);
+             _f("No accounts, and no past transaction matching '%1%'")
+             % tmpl->payee_mask);
     }
   } else {
     DEBUG("draft.xact", "Template had postings");
diff --git a/src/error.cc b/src/error.cc
index 4a16f4e3..58339db7 100644
--- a/src/error.cc
+++ b/src/error.cc
@@ -35,9 +35,7 @@
 
 namespace ledger {
 
-straccstream       _ctxt_accum;
 std::ostringstream _ctxt_buffer;
-straccstream       _desc_accum;
 std::ostringstream _desc_buffer;
 
 string error_context()
diff --git a/src/error.h b/src/error.h
index 86d9de76..9837fa4d 100644
--- a/src/error.h
+++ b/src/error.h
@@ -42,11 +42,8 @@
 #ifndef _ERROR_H
 #define _ERROR_H
 
-#include "accum.h"
-
 namespace ledger {
 
-extern straccstream       _desc_accum;
 extern std::ostringstream _desc_buffer;
 
 template <typename T>
@@ -57,8 +54,7 @@ inline void throw_func(const string& message) {
 }
 
 #define throw_(cls, msg)                        \
-  ((_desc_buffer << ACCUM(_desc_accum << msg)), \
-   _desc_accum.clear(),                         \
+  ((_desc_buffer << (msg)),                     \
    throw_func<cls>(_desc_buffer.str()))
 
 inline void warning_func(const string& message) {
@@ -68,19 +64,15 @@ inline void warning_func(const string& message) {
 }
 
 #define warning_(msg)                           \
-  ((_desc_buffer << ACCUM(_desc_accum << msg)), \
-   _desc_accum.clear(),                         \
+  ((_desc_buffer << (msg)),                     \
    warning_func(_desc_buffer.str()))
 
-extern straccstream       _ctxt_accum;
 extern std::ostringstream _ctxt_buffer;
 
-#define add_error_context(msg)                                  \
-  ((long(_ctxt_buffer.tellp()) == 0) ?                          \
-   ((_ctxt_buffer << ACCUM(_ctxt_accum << msg)),                \
-    _ctxt_accum.clear()) :                                      \
-   ((_ctxt_buffer << std::endl << ACCUM(_ctxt_accum << msg)),   \
-    _ctxt_accum.clear()))
+#define add_error_context(msg)                  \
+  ((long(_ctxt_buffer.tellp()) == 0) ?          \
+   (_ctxt_buffer << (msg)) :                    \
+   (_ctxt_buffer << std::endl << (msg)))
 
 string error_context();
 
diff --git a/src/expr.cc b/src/expr.cc
index 25967207..dbe860bf 100644
--- a/src/expr.cc
+++ b/src/expr.cc
@@ -306,8 +306,8 @@ value_t source_command(call_scope_t& args)
         expr_t(p).calc(file_locals);
       }
       catch (const std::exception&) {
-        add_error_context(_("While parsing value expression on line %1:")
-                          << linenum);
+        add_error_context(_f("While parsing value expression on line %1%:")
+                          % linenum);
         add_error_context(source_context(pathname, pos, in->tellg(), "> "));
       }
     }
diff --git a/src/format.cc b/src/format.cc
index 8c3cbc14..18c7696d 100644
--- a/src/format.cc
+++ b/src/format.cc
@@ -236,7 +236,7 @@ format_t::element_t * format_t::parse_elements(const string& fmt,
         }
       }
       if (! found)
-        throw_(format_error, _("Unrecognized formatting character: %1") << *p);
+        throw_(format_error, _f("Unrecognized formatting character: %1%") % *p);
     } else {
       switch (*p) {
       case '%':
@@ -375,7 +375,7 @@ format_t::element_t * format_t::parse_elements(const string& fmt,
       }
 
       default:
-        throw_(format_error, _("Unrecognized formatting character: %1") << *p);
+        throw_(format_error, _f("Unrecognized formatting character: %1%") % *p);
       }
     }
   }
diff --git a/src/generate.cc b/src/generate.cc
index 8769c99c..bcbde9f1 100644
--- a/src/generate.cc
+++ b/src/generate.cc
@@ -374,14 +374,14 @@ void generate_posts_iterator::increment()
       }
     }
     catch (std::exception&) {
-      add_error_context(_("While parsing generated transaction (seed %1):")
-                        << seed);
+      add_error_context(_f("While parsing generated transaction (seed %1%):")
+                        % seed);
       add_error_context(buf.str());
       throw;
     }
     catch (int) {
-      add_error_context(_("While parsing generated transaction (seed %1):")
-                        << seed);
+      add_error_context(_f("While parsing generated transaction (seed %1%):")
+                        % seed);
       add_error_context(buf.str());
       throw;
     }
diff --git a/src/global.cc b/src/global.cc
index 6dc8d150..285fdea3 100644
--- a/src/global.cc
+++ b/src/global.cc
@@ -121,8 +121,8 @@ void global_scope_t::read_init()
       if (session().journal->read(parsing_context) > 0 ||
           session().journal->auto_xacts.size() > 0 ||
           session().journal->period_xacts.size() > 0) {
-        throw_(parse_error, _("Transactions found in initialization file '%1'")
-               << init_file);
+        throw_(parse_error, _f("Transactions found in initialization file '%1%'")
+               % init_file);
       }
 
       TRACE_FINISH(init, 1);
@@ -203,7 +203,7 @@ void global_scope_t::execute_command(strings_list args, bool at_repl)
     report().normalize_options(verb);
 
     if (! bool(command = look_for_command(bound_scope, verb)))
-      throw_(std::logic_error, _("Unrecognized command '%1'") << verb);
+      throw_(std::logic_error, _f("Unrecognized command '%1%'") % verb);
   }
 
   // Create the output stream (it might be a file, the console or a PAGER
diff --git a/src/item.cc b/src/item.cc
index 17d46652..de5ffef2 100644
--- a/src/item.cc
+++ b/src/item.cc
@@ -270,16 +270,16 @@ namespace {
         return item.has_tag(args.get<mask_t>(0));
       else
         throw_(std::runtime_error,
-               _("Expected string or mask for argument 1, but received %1")
-               << args[0].label());
+               _f("Expected string or mask for argument 1, but received %1%")
+               % args[0].label());
     }
     else if (args.size() == 2) {
       if (args[0].is_mask() && args[1].is_mask())
         return item.has_tag(args.get<mask_t>(0), args.get<mask_t>(1));
       else
         throw_(std::runtime_error,
-               _("Expected masks for arguments 1 and 2, but received %1 and %2")
-               << args[0].label() << args[1].label());
+               _f("Expected masks for arguments 1 and 2, but received %1% and %2%")
+               % args[0].label() % args[1].label());
     }
     else if (args.size() == 0) {
       throw_(std::runtime_error, _("Too few arguments to function"));
@@ -302,16 +302,16 @@ namespace {
         val = item.get_tag(args.get<mask_t>(0));
       else
         throw_(std::runtime_error,
-               _("Expected string or mask for argument 1, but received %1")
-               << args[0].label());
+               _f("Expected string or mask for argument 1, but received %1%")
+               % args[0].label());
     }
     else if (args.size() == 2) {
       if (args[0].is_mask() && args[1].is_mask())
         val = item.get_tag(args.get<mask_t>(0), args.get<mask_t>(1));
       else
         throw_(std::runtime_error,
-               _("Expected masks for arguments 1 and 2, but received %1 and %2")
-               << args[0].label() << args[1].label());
+               _f("Expected masks for arguments 1 and 2, but received %1% and %2%")
+               % args[0].label() % args[1].label());
     }
     else if (args.size() == 0) {
       throw_(std::runtime_error, _("Too few arguments to function"));
diff --git a/src/journal.cc b/src/journal.cc
index 49d86ff0..e6c09125 100644
--- a/src/journal.cc
+++ b/src/journal.cc
@@ -160,11 +160,10 @@ account_t * journal_t::register_account(const string& name, post_t * post,
         result->add_flags(ACCOUNT_KNOWN);
       }
       else if (checking_style == CHECK_WARNING) {
-        current_context->warning(STR(_("Unknown account '%1'")
-                                     << result->fullname()));
+        current_context->warning(_f("Unknown account '%1%'") % result->fullname());
       }
       else if (checking_style == CHECK_ERROR) {
-        throw_(parse_error, _("Unknown account '%1'") << result->fullname());
+        throw_(parse_error, _f("Unknown account '%1%'") % result->fullname());
       }
     }
   }
@@ -190,10 +189,10 @@ string journal_t::register_payee(const string& name, xact_t * xact)
         known_payees.insert(name);
       }
       else if (checking_style == CHECK_WARNING) {
-        current_context->warning(STR(_("Unknown payee '%1'") << name));
+        current_context->warning(_f("Unknown payee '%1%'") % name);
       }
       else if (checking_style == CHECK_ERROR) {
-        throw_(parse_error, _("Unknown payee '%1'") << name);
+        throw_(parse_error, _f("Unknown payee '%1%'") % name);
       }
     }
   }
@@ -226,10 +225,10 @@ void journal_t::register_commodity(commodity_t& comm,
         comm.add_flags(COMMODITY_KNOWN);
       }
       else if (checking_style == CHECK_WARNING) {
-        current_context->warning(STR(_("Unknown commodity '%1'") << comm));
+        current_context->warning(_f("Unknown commodity '%1%'") % comm);
       }
       else if (checking_style == CHECK_ERROR) {
-        throw_(parse_error, _("Unknown commodity '%1'") << comm);
+        throw_(parse_error, _f("Unknown commodity '%1%'") % comm);
       }
     }
   }
@@ -255,10 +254,10 @@ void journal_t::register_metadata(const string& key, const value_t& value,
         known_tags.insert(key);
       }
       else if (checking_style == CHECK_WARNING) {
-        current_context->warning(STR(_("Unknown metadata tag '%1'") << key));
+        current_context->warning(_f("Unknown metadata tag '%1%'") % key);
       }
       else if (checking_style == CHECK_ERROR) {
-        throw_(parse_error, _("Unknown metadata tag '%1'") << key);
+        throw_(parse_error, _f("Unknown metadata tag '%1%'") % key);
       }
     }
   }
@@ -281,12 +280,12 @@ void journal_t::register_metadata(const string& key, const value_t& value,
       if (! (*i).second.first.calc(val_scope).to_boolean()) {
         if ((*i).second.second == expr_t::EXPR_ASSERTION)
           throw_(parse_error,
-                 _("Metadata assertion failed for (%1: %2): %3")
-                 << key << value << (*i).second.first);
+                 _f("Metadata assertion failed for (%1%: %2%): %3%")
+                 % key % value % (*i).second.first);
         else
           current_context->warning
-            (STR(_("Metadata check failed for (%1: %2): %3")
-                 << key << value << (*i).second.first));
+            (_f("Metadata check failed for (%1%: %2%): %3%")
+             % key % value % (*i).second.first);
       }
     }
   }
@@ -388,8 +387,8 @@ std::size_t journal_t::read(parse_context_stack_t& context)
 
     if (! current.scope)
       throw_(std::runtime_error,
-             _("No default scope in which to read journal file '%1'")
-             << current.pathname);
+             _f("No default scope in which to read journal file '%1%'")
+             % current.pathname);
 
     if (! current.master)
       current.master = master;
diff --git a/src/main.cc b/src/main.cc
index 0130d5c6..b309255b 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -146,7 +146,7 @@ int main(int argc, char * argv[], char * envp[])
             std::free(expansion);
           std::free(p);
           throw_(std::logic_error,
-                 _("Failed to expand history reference '%1'") << p);
+                 _f("Failed to expand history reference '%1%'") % p);
         }
         else if (expansion) {
           add_history(expansion);
diff --git a/src/op.cc b/src/op.cc
index 8be0796a..6ba921e5 100644
--- a/src/op.cc
+++ b/src/op.cc
@@ -79,9 +79,9 @@ namespace {
         scope.type_context() != value_t::VOID &&
         result.type() != scope.type_context()) {
       throw_(calc_error,
-             _("Expected return of %1, but received %2")
-             << result.label(scope.type_context())
-             << result.label());
+             _f("Expected return of %1%, but received %2%")
+             % result.label(scope.type_context())
+             % result.label());
     }
   }
 }
@@ -181,7 +181,7 @@ expr_t::ptr_op_t expr_t::op_t::compile(scope_t& scope, const int depth,
         std::ostringstream buf;
         varname->dump(buf, 0);
         throw_(calc_error,
-               _("Invalid function or lambda parameter: %1") << buf.str());
+               _f("Invalid function or lambda parameter: %1%") % buf.str());
       } else {
         DEBUG("expr.compile",
               "Defining function parameter " << varname->as_ident());
@@ -242,7 +242,7 @@ namespace {
       def = scope.lookup(symbol_t::FUNCTION, op->as_ident());
     }
     if (! def)
-      throw_(calc_error, _("Unknown identifier '%1'") << op->as_ident());
+      throw_(calc_error, _f("Unknown identifier '%1%'") % op->as_ident());
     return def;
   }
 }
@@ -412,7 +412,7 @@ value_t expr_t::op_t::calc(scope_t& scope, ptr_op_t * locus, const int depth)
     break;
 
   default:
-    throw_(calc_error, _("Unexpected expr node '%1'") << op_context(this));
+    throw_(calc_error, _f("Unexpected expr node '%1%'") % op_context(this));
   }
 
 #if defined(DEBUG_ON)
@@ -462,7 +462,7 @@ namespace {
         return find_definition(as_expr(def), scope, locus, depth,
                                recursion_depth + 1);
       else
-        throw_(value_error, _("Cannot call %1 as a function") << def.label());
+        throw_(value_error, _f("Cannot call %1% as a function") % def.label());
     }
 
     // Resolve ordinary expressions.
@@ -504,8 +504,8 @@ namespace {
 
     if (args_index < args_count)
       throw_(calc_error,
-             _("Too few arguments in function call (saw %1, wanted %2)")
-             << args_count << args_index);
+             _f("Too few arguments in function call (saw %1%, wanted %2%)")
+             % args_count % args_index);
 
     if (func->right()->is_scope()) {
       bind_scope_t outer_scope(scope, *func->right()->as_scope());
@@ -555,8 +555,8 @@ value_t expr_t::op_t::calc_call(scope_t& scope, ptr_op_t * locus,
     }
   }
   catch (const std::exception&) {
-    add_error_context(_("While calling function '%1 %2':" << name
-                        << call_args.args));
+    add_error_context(_f("While calling function '%1% %2%':") % name
+                      % call_args.args);
     throw;
   }
 }
diff --git a/src/option.cc b/src/option.cc
index 418980bd..7fcc9e4d 100644
--- a/src/option.cc
+++ b/src/option.cc
@@ -88,9 +88,9 @@ namespace {
     }
     catch (const std::exception&) {
       if (name[0] == '-')
-        add_error_context(_("While parsing option '%1'") << name);
+        add_error_context(_f("While parsing option '%1%'") % name);
       else
-        add_error_context(_("While parsing environent variable '%1'") << name);
+        add_error_context(_f("While parsing environent variable '%1%'") % name);
       throw;
     }
   }
@@ -137,8 +137,8 @@ void process_environment(const char ** envp, const string& tag,
             process_option(string("$") + buf, string(buf), scope, q + 1, value);
         }
         catch (const std::exception&) {
-          add_error_context(_("While parsing environment variable option '%1':")
-                            << *p);
+          add_error_context(_f("While parsing environment variable option '%1%':")
+                            % *p);
           throw;
         }
       }
@@ -198,20 +198,20 @@ strings_list process_arguments(strings_list args, scope_t& scope)
 
       op_bool_tuple opt(find_option(scope, opt_name));
       if (! opt.first)
-        throw_(option_error, _("Illegal option --%1") << name);
+        throw_(option_error, _f("Illegal option --%1%") % name);
 
       if (opt.second && ! value && ++i != args.end() && value == NULL) {
         value = (*i).c_str();
         DEBUG("option.args", "  read option value from arg: " << value);
         if (value == NULL)
-          throw_(option_error, _("Missing option argument for --%1") << name);
+          throw_(option_error, _f("Missing option argument for --%1%") % name);
       }
       process_option(string("--") + name,
                      opt.first->as_function(), scope, value,
                      string("--") + name);
     }
     else if ((*i)[1] == '\0') {
-      throw_(option_error, _("illegal option -%1") << (*i)[0]);
+      throw_(option_error, _f("illegal option -%1%") % (*i)[0]);
     }
     else {
       DEBUG("option.args", "  single-char option");
@@ -222,7 +222,7 @@ strings_list process_arguments(strings_list args, scope_t& scope)
       for (char c = (*i)[x]; c != '\0'; x++, c = (*i)[x]) {
         op_bool_tuple opt(find_option(scope, c));
         if (! opt.first)
-          throw_(option_error, _("Illegal option -%1") << c);
+          throw_(option_error, _f("Illegal option -%1%") % c);
 
         option_queue.push_back(op_bool_char_tuple(opt.first, opt.second, c));
       }
@@ -234,7 +234,7 @@ strings_list process_arguments(strings_list args, scope_t& scope)
           DEBUG("option.args", "  read option value from arg: " << value);
           if (value == NULL)
             throw_(option_error,
-                   _("Missing option argument for -%1") << o.ch);
+                   _f("Missing option argument for -%1%") % o.ch);
         }
         process_option(string("-") + o.ch, o.op->as_function(), scope, value,
                        string("-") + o.ch);
diff --git a/src/option.h b/src/option.h
index b0d4e0f0..80be69c4 100644
--- a/src/option.h
+++ b/src/option.h
@@ -127,7 +127,7 @@ public:
   string str() const {
     assert(handled);
     if (value.empty())
-      throw_(std::runtime_error, _("No argument provided for %1") << desc());
+      throw_(std::runtime_error, _f("No argument provided for %1%") % desc());
     return value;
   }
 
@@ -168,18 +168,18 @@ public:
   value_t handler(call_scope_t& args) {
     if (wants_arg) {
       if (args.size() < 2)
-        throw_(std::runtime_error, _("No argument provided for %1") << desc());
+        throw_(std::runtime_error, _f("No argument provided for %1%") % desc());
       else if (args.size() > 2)
-        throw_(std::runtime_error, _("To many arguments provided for %1") << desc());
+        throw_(std::runtime_error, _f("To many arguments provided for %1%") % desc());
       else if (! args[0].is_string())
-        throw_(std::runtime_error, _("Context argument for %1 not a string") << desc());
+        throw_(std::runtime_error, _f("Context argument for %1% not a string") % desc());
       on(args.get<string>(0), args.get<string>(1));
     }
     else if (args.size() < 1) {
-      throw_(std::runtime_error, _("No argument provided for %1") << desc());
+      throw_(std::runtime_error, _f("No argument provided for %1%") % desc());
     }
     else if (! args[0].is_string()) {
-      throw_(std::runtime_error, _("Context argument for %1 not a string") << desc());
+      throw_(std::runtime_error, _f("Context argument for %1% not a string") % desc());
     }
     else {
       on(args.get<string>(0));
diff --git a/src/parser.cc b/src/parser.cc
index 360ac93d..a17ad271 100644
--- a/src/parser.cc
+++ b/src/parser.cc
@@ -113,7 +113,7 @@ expr_t::parser_t::parse_dot_expr(std::istream& in,
         node->set_right(parse_call_expr(in, tflags));
         if (! node->right())
           throw_(parse_error,
-                 _("%1 operator not followed by argument") << tok.symbol);
+                 _f("%1% operator not followed by argument") % tok.symbol);
       } else {
         push_token(tok);
         break;
@@ -137,7 +137,7 @@ expr_t::parser_t::parse_unary_expr(std::istream& in,
     ptr_op_t term(parse_dot_expr(in, tflags));
     if (! term)
       throw_(parse_error,
-             _("%1 operator not followed by argument") << tok.symbol);
+             _f("%1% operator not followed by argument") % tok.symbol);
 
     // A very quick optimization
     if (term->kind == op_t::VALUE) {
@@ -154,7 +154,7 @@ expr_t::parser_t::parse_unary_expr(std::istream& in,
     ptr_op_t term(parse_dot_expr(in, tflags));
     if (! term)
       throw_(parse_error,
-             _("%1 operator not followed by argument") << tok.symbol);
+             _f("%1% operator not followed by argument") % tok.symbol);
 
     // A very quick optimization
     if (term->kind == op_t::VALUE) {
@@ -195,7 +195,7 @@ expr_t::parser_t::parse_mul_expr(std::istream& in,
         node->set_right(parse_unary_expr(in, tflags));
         if (! node->right())
           throw_(parse_error,
-                 _("%1 operator not followed by argument") << tok.symbol);
+                 _f("%1% operator not followed by argument") % tok.symbol);
       } else {
         push_token(tok);
         break;
@@ -225,7 +225,7 @@ expr_t::parser_t::parse_add_expr(std::istream& in,
         node->set_right(parse_mul_expr(in, tflags));
         if (! node->right())
           throw_(parse_error,
-                 _("%1 operator not followed by argument") << tok.symbol);
+                 _f("%1% operator not followed by argument") % tok.symbol);
       } else {
         push_token(tok);
         break;
@@ -292,7 +292,7 @@ expr_t::parser_t::parse_logic_expr(std::istream& in,
 
         if (! node->right())
           throw_(parse_error,
-                 _("%1 operator not followed by argument") << tok.symbol);
+                 _f("%1% operator not followed by argument") % tok.symbol);
 
         if (negate) {
           prev = node;
@@ -324,7 +324,7 @@ expr_t::parser_t::parse_and_expr(std::istream& in,
         node->set_right(parse_logic_expr(in, tflags));
         if (! node->right())
           throw_(parse_error,
-                 _("%1 operator not followed by argument") << tok.symbol);
+                 _f("%1% operator not followed by argument") % tok.symbol);
       } else {
         push_token(tok);
         break;
@@ -351,7 +351,7 @@ expr_t::parser_t::parse_or_expr(std::istream& in,
         node->set_right(parse_and_expr(in, tflags));
         if (! node->right())
           throw_(parse_error,
-                 _("%1 operator not followed by argument") << tok.symbol);
+                 _f("%1% operator not followed by argument") % tok.symbol);
       } else {
         push_token(tok);
         break;
@@ -377,7 +377,7 @@ expr_t::parser_t::parse_querycolon_expr(std::istream& in,
       node->set_right(parse_or_expr(in, tflags));
       if (! node->right())
         throw_(parse_error,
-               _("%1 operator not followed by argument") << tok.symbol);
+               _f("%1% operator not followed by argument") % tok.symbol);
 
       next_token(in, tflags.plus_flags(PARSE_OP_CONTEXT), token_t::COLON);
       prev = node->right();
@@ -386,7 +386,7 @@ expr_t::parser_t::parse_querycolon_expr(std::istream& in,
       subnode->set_right(parse_or_expr(in, tflags));
       if (! subnode->right())
         throw_(parse_error,
-               _("%1 operator not followed by argument") << tok.symbol);
+               _f("%1% operator not followed by argument") % tok.symbol);
 
       node->set_right(subnode);
     }
diff --git a/src/post.cc b/src/post.cc
index 0564eaca..e89c0e7c 100644
--- a/src/post.cc
+++ b/src/post.cc
@@ -292,13 +292,13 @@ namespace {
         }
         else {
           throw_(std::runtime_error,
-                 _("Expected string or mask for argument 1, but received %1")
-                 << args[0].label());
+                 _f("Expected string or mask for argument 1, but received %1%")
+                 % args[0].label());
         }
 
         if (! acct)
           throw_(std::runtime_error,
-                 _("Could not find an account matching ") << args[0]);
+                 _f("Could not find an account matching '%1%'") % args[0]);
 
         return value_t(static_cast<scope_t *>(acct));
       }
diff --git a/src/post.h b/src/post.h
index 78928f23..f4bff01f 100644
--- a/src/post.h
+++ b/src/post.h
@@ -106,7 +106,7 @@ public:
   virtual string description() {
     if (pos) {
       std::ostringstream buf;
-      buf << _("posting at line %1") << pos->beg_line;
+      buf << _f("posting at line %1") << pos->beg_line;
       return buf.str();
     } else {
       return string(_("generated posting"));
diff --git a/src/pyinterp.cc b/src/pyinterp.cc
index 8d9c8c84..3c864910 100644
--- a/src/pyinterp.cc
+++ b/src/pyinterp.cc
@@ -113,12 +113,12 @@ void python_module_t::import_module(const string& name, bool import_direct)
   object mod = python::import(name.c_str());
   if (! mod)
     throw_(std::runtime_error,
-           _("Module import failed (couldn't find %1)") << name);
+           _f("Module import failed (couldn't find %1%)") % name);
 
   dict globals = extract<dict>(mod.attr("__dict__"));
   if (! globals)
     throw_(std::runtime_error,
-           _("Module import failed (couldn't find %1)") << name);
+           _f("Module import failed (couldn't find %1%)") % name);
 
   if (! import_direct) {
     module_object  = mod;
@@ -246,7 +246,7 @@ object python_interpreter_t::import_option(const string& str)
   }
   catch (const error_already_set&) {
     PyErr_Print();
-    throw_(std::runtime_error, _("Python failed to import: %1") << str);
+    throw_(std::runtime_error, _f("Python failed to import: %1%") % str);
   }
   catch (...) {
     throw;
@@ -582,7 +582,7 @@ value_t python_interpreter_t::functor_t::operator()(call_scope_t& args)
       }
       else if (PyErr_Occurred()) {
         PyErr_Print();
-        throw_(calc_error, _("Failed call to Python function '%1'") << name);
+        throw_(calc_error, _f("Failed call to Python function '%1%'") % name);
       } else {
         assert(false);
       }
@@ -595,7 +595,7 @@ value_t python_interpreter_t::functor_t::operator()(call_scope_t& args)
   catch (const error_already_set&) {
     std::signal(SIGINT, sigint_handler);
     PyErr_Print();
-    throw_(calc_error, _("Failed call to Python function '%1'") << name);
+    throw_(calc_error, _f("Failed call to Python function '%1%'") % name);
   }
   catch (...) {
     std::signal(SIGINT, sigint_handler);
diff --git a/src/query.cc b/src/query.cc
index 3fec708a..07f724fd 100644
--- a/src/query.cc
+++ b/src/query.cc
@@ -79,7 +79,7 @@ query_t::lexer_t::next_token(query_t::lexer_t::token_t::kind_t tok_context)
       pat.push_back(*arg_i);
     }
     if (! found_closing)
-      throw_(parse_error, _("Expected '%1' at end of pattern") << closing);
+      throw_(parse_error, _f("Expected '%1%' at end of pattern") % closing);
     if (pat.empty())
       throw_(parse_error, _("Match pattern is empty"));
 
@@ -229,9 +229,9 @@ void query_t::lexer_t::token_t::unexpected()
   case END_REACHED:
     throw_(parse_error, _("Unexpected end of expression"));
   case TERM:
-    throw_(parse_error, _("Unexpected string '%1'") << *value);
+    throw_(parse_error, _f("Unexpected string '%1%'") % *value);
   default:
-    throw_(parse_error, _("Unexpected token '%1'") << symbol());
+    throw_(parse_error, _f("Unexpected token '%1%'") % symbol());
   }
 }
 
@@ -243,12 +243,12 @@ void query_t::lexer_t::token_t::expected(char wanted, char c)
     if (wanted == '\0' || wanted == -1)
       throw_(parse_error, _("Unexpected end"));
     else
-      throw_(parse_error, _("Missing '%1'") << wanted);
+      throw_(parse_error, _f("Missing '%1%'") % wanted);
   } else {
     if (wanted == '\0' || wanted == -1)
-      throw_(parse_error, _("Invalid char '%1'") << c);
+      throw_(parse_error, _f("Invalid char '%1%'") % c);
     else
-      throw_(parse_error, _("Invalid char '%1' (wanted '%2')") << c << wanted);
+      throw_(parse_error, _f("Invalid char '%1%' (wanted '%2%')") % c % wanted);
   }
 }
 
@@ -278,7 +278,7 @@ query_t::parser_t::parse_query_term(query_t::lexer_t::token_t::kind_t tok_contex
     node = parse_query_term(tok.kind);
     if (! node)
       throw_(parse_error,
-             _("%1 operator not followed by argument") << tok.symbol());
+             _f("%1% operator not followed by argument") % tok.symbol());
     break;
 
   case lexer_t::token_t::TERM:
@@ -374,7 +374,7 @@ query_t::parser_t::parse_unary_expr(lexer_t::token_t::kind_t tok_context)
     expr_t::ptr_op_t term(parse_query_term(tok_context));
     if (! term)
       throw_(parse_error,
-             _("%1 operator not followed by argument") << tok.symbol());
+             _f("%1% operator not followed by argument") % tok.symbol());
 
     node = new expr_t::op_t(expr_t::op_t::O_NOT);
     node->set_left(term);
@@ -403,7 +403,7 @@ query_t::parser_t::parse_and_expr(lexer_t::token_t::kind_t tok_context)
         node->set_right(parse_unary_expr(tok_context));
         if (! node->right())
           throw_(parse_error,
-                 _("%1 operator not followed by argument") << tok.symbol());
+                 _f("%1% operator not followed by argument") % tok.symbol());
       } else {
         lexer.push_token(tok);
         break;
@@ -427,7 +427,7 @@ query_t::parser_t::parse_or_expr(lexer_t::token_t::kind_t tok_context)
         node->set_right(parse_and_expr(tok_context));
         if (! node->right())
           throw_(parse_error,
-                 _("%1 operator not followed by argument") << tok.symbol());
+                 _f("%1% operator not followed by argument") % tok.symbol());
       } else {
         lexer.push_token(tok);
         break;
diff --git a/src/report.cc b/src/report.cc
index c7559cf7..c80a2f0f 100644
--- a/src/report.cc
+++ b/src/report.cc
@@ -591,15 +591,15 @@ value_t report_t::fn_get_at(call_scope_t& args)
   }
   else if (! args[0].is_sequence()) {
     throw_(std::runtime_error,
-           _("Attempting to get argument at index %1 from %2")
-           << index << args[0].label());
+           _f("Attempting to get argument at index %1% from %2%")
+           % index % args[0].label());
   }
 
   value_t::sequence_t& seq(args[0].as_sequence_lval());
   if (index >= seq.size())
     throw_(std::runtime_error,
-           _("Attempting to get index %1 from %2 with %3 elements")
-           << index << args[0].label() << seq.size());
+           _f("Attempting to get index %1% from %2% with %3% elements")
+           % index % args[0].label() % seq.size());
 
   return seq[index];
 }
@@ -852,8 +852,8 @@ value_t report_t::fn_nail_down(call_scope_t& args)
   }
 
   default:
-    throw_(std::runtime_error, _("Attempting to nail down %1")
-           << args[0].label());
+    throw_(std::runtime_error, _f("Attempting to nail down %1%")
+           % args[0].label());
   }
   return arg0;
 }
diff --git a/src/report.h b/src/report.h
index d04b3e15..085cfa48 100644
--- a/src/report.h
+++ b/src/report.h
@@ -434,7 +434,7 @@ public:
         OTHER(limit_).on(whence, predicate);
       } else {
         throw_(std::invalid_argument,
-               _("Could not determine beginning of period '%1'") << str);
+               _f("Could not determine beginning of period '%1%'") % str);
       }
     });
 
@@ -651,8 +651,8 @@ public:
         parent->terminus = datetime_t(*end);
       } else {
         throw_(std::invalid_argument,
-               _("Could not determine end of period '%1'")
-               << str);
+               _f("Could not determine end of period '%1%'")
+               % str);
       }
     });
 
@@ -770,8 +770,8 @@ public:
         ledger::epoch = parent->terminus = datetime_t(*begin);
       } else {
         throw_(std::invalid_argument,
-               _("Could not determine beginning of period '%1'")
-               << str);
+               _f("Could not determine beginning of period '%1%'")
+               % str);
       }
     });
 
@@ -1002,7 +1002,7 @@ public:
         format_t::default_style = format_t::TRUNCATE_TRAILING;
       else
         throw_(std::invalid_argument,
-               _("Unrecognized truncation style: '%1'") << style);
+               _f("Unrecognized truncation style: '%1%'") % style);
       format_t::default_style_changed = true;
     });
 
diff --git a/src/scope.cc b/src/scope.cc
index 00327159..9112040c 100644
--- a/src/scope.cc
+++ b/src/scope.cc
@@ -58,7 +58,7 @@ void symbol_scope_t::define(const symbol_t::kind_t kind,
                              (symbol_t(kind, name, def), def));
     if (! result.second)
       throw_(compile_error,
-             _("Redefinition of '%1' in the same scope") << name);
+             _f("Redefinition of '%1%' in the same scope") % name);
   }
 }
 
@@ -88,8 +88,8 @@ value_t& call_scope_t::resolve(const std::size_t index,
     context_scope_t scope(*this, context, required);
     value = as_expr(value)->calc(scope, locus, depth);
     if (required && ! value.is_type(context))
-      throw_(calc_error, _("Expected %1 for argument %2, but received %3")
-             << value.label(context) << index << value.label());
+      throw_(calc_error, _f("Expected %1% for argument %2%, but received %3%")
+             % value.label(context) % index % value.label());
   }
   return value;
 }
diff --git a/src/stats.cc b/src/stats.cc
index 0966fee2..a12420b6 100644
--- a/src/stats.cc
+++ b/src/stats.cc
@@ -55,15 +55,12 @@ value_t report_statistics(call_scope_t& args)
   assert(is_valid(statistics.earliest_post));
   assert(is_valid(statistics.latest_post));
 
-  {
-    straccstream accum;
-    out << ACCUM(accum << _("Time period: %1 to %2 (%3 days)")
-                 << format_date(statistics.earliest_post)
-                 << format_date(statistics.latest_post)
-                 << (statistics.latest_post -
-                     statistics.earliest_post).days())
-        << std::endl << std::endl;
-  }
+  out << format(_f("Time period: %1% to %2% (%3% days)")
+                % format_date(statistics.earliest_post)
+                % format_date(statistics.latest_post)
+                % (statistics.latest_post -
+                   statistics.earliest_post).days())
+      << std::endl << std::endl;
 
   out << _("  Files these postings came from:") << std::endl;
 
diff --git a/src/system.hh.in b/src/system.hh.in
index 552a591a..8b8fef7f 100644
--- a/src/system.hh.in
+++ b/src/system.hh.in
@@ -117,12 +117,6 @@ typedef std::ostream::pos_type ostream_pos_type;
 #include <sys/types.h>
 #include <sys/wait.h>
 #endif
-#if defined(HAVE_GETTEXT)
-#include "gettext.h"
-#define _(str) gettext(str)
-#else
-#define _(str) str
-#endif
 
 #include <gmp.h>
 #include <mpfr.h>
@@ -152,6 +146,8 @@ typedef std::ostream::pos_type ostream_pos_type;
 #if !(defined(__GXX_EXPERIMENTAL_CXX0X__) && __GXX_EXPERIMENTAL_CXX0X__)
 #include <boost/foreach.hpp>
 #endif
+
+#include <boost/format.hpp>
 #include <boost/function.hpp>
 
 #include <boost/graph/adjacency_list.hpp>
@@ -193,6 +189,15 @@ typedef std::ostream::pos_type ostream_pos_type;
 #include <boost/variant.hpp>
 #include <boost/version.hpp>
 
+#if defined(HAVE_GETTEXT)
+#include "gettext.h"
+#define _(str) gettext(str)
+#define _f(str) boost::format(gettext(str))
+#else
+#define _(str) str
+#define _f(str) boost::format(str)
+#endif
+
 #if defined(HAVE_BOOST_SERIALIZATION)
 
 #include <boost/archive/binary_iarchive.hpp>
diff --git a/src/textual.cc b/src/textual.cc
index 011e45b7..1665d4dd 100644
--- a/src/textual.cc
+++ b/src/textual.cc
@@ -271,10 +271,10 @@ void instance_t::parse()
           instances.push_front(instance);
 
         foreach (instance_t * instance, instances)
-          add_error_context(_("In file included from %1")
-                            << instance->context.location());
+          add_error_context(_f("In file included from %1%")
+                            % instance->context.location());
       }
-      add_error_context(_("While parsing file %1") << context.location());
+      add_error_context(_f("While parsing file %1%") % context.location());
 
       if (caught_signal != NONE_CAUGHT)
         throw;
@@ -544,7 +544,7 @@ void instance_t::option_directive(char * line)
   path abs_path(filesystem::absolute(context.pathname,
                                      context.current_directory));
   if (! process_option(abs_path.string(), line + 2, *context.scope, p, line))
-    throw_(option_error, _("Illegal option --%1") << line + 2);
+    throw_(option_error, _f("Illegal option --%1%") % (line + 2));
 }
 
 void instance_t::automated_xact_directive(char * line)
@@ -813,7 +813,7 @@ void instance_t::include_directive(char * line)
 
   if (! files_found)
     throw_(std::runtime_error,
-           _("File to include was not found: %1") << filename);
+           _f("File to include was not found: %1%") % filename);
 
 }
 
@@ -886,15 +886,15 @@ void instance_t::end_apply_directive(char * kind)
              _("'end' or 'end apply' found, but no enclosing 'apply' directive"));
     } else {
       throw_(std::runtime_error,
-             _("'end apply %1' found, but no enclosing 'apply' directive")
-             << name);
+             _f("'end apply %1%' found, but no enclosing 'apply' directive")
+             % name);
     }
   }
 
   if (! name.empty() && name != apply_stack.front().label)
     throw_(std::runtime_error,
-           _("'end apply %1' directive does not match 'apply %2' directive")
-           << name << apply_stack.front().label);
+           _f("'end apply %1%' directive does not match 'apply %2%' directive")
+           % name % apply_stack.front().label);
 
   if (apply_stack.front().value.type() == typeid(optional<datetime_t>))
     epoch = boost::get<optional<datetime_t> >(apply_stack.front().value);
@@ -1142,14 +1142,14 @@ void instance_t::assert_directive(char * line)
 {
   expr_t expr(line);
   if (! expr.calc(*context.scope).to_boolean())
-    throw_(parse_error, _("Assertion failed: %1") << line);
+    throw_(parse_error, _f("Assertion failed: %1%") % line);
 }
 
 void instance_t::check_directive(char * line)
 {
   expr_t expr(line);
   if (! expr.calc(*context.scope).to_boolean())
-    context.warning(STR(_("Check failed: %1") << line));
+    context.warning(_f("Check failed: %1%") % line);
 }
 
 void instance_t::value_directive(char * line)
@@ -1624,7 +1624,7 @@ post_t * instance_t::parse_post(char *          line,
         if (! post->amount.is_null()) {
           diff -= post->amount;
           if (! diff.is_zero())
-            throw_(parse_error, _("Balance assertion off by %1") << diff);
+            throw_(parse_error, _f("Balance assertion off by %1%") % diff);
         } else {
           post->amount = diff;
           DEBUG("textual.parse", "line " << context.linenum << ": "
@@ -1654,8 +1654,8 @@ post_t * instance_t::parse_post(char *          line,
 
   if (next && *next)
     throw_(parse_error,
-           _("Unexpected char '%1' (Note: inline math requires parentheses)")
-           << *next);
+           _f("Unexpected char '%1%' (Note: inline math requires parentheses)")
+           % *next);
 
   post->pos->end_pos  = context.curr_pos;
   post->pos->end_line = context.linenum;
@@ -1838,9 +1838,9 @@ xact_t * instance_t::parse_xact(char *          line,
       }
       else if (! expr.calc(bound_scope).to_boolean()) {
         if (c == 'a') {
-          throw_(parse_error, _("Transaction assertion failed: %1") << p);
+          throw_(parse_error, _f("Transaction assertion failed: %1%") % p);
         } else {
-          context.warning(STR(_("Transaction check failed: %1") << p));
+          context.warning(_f("Transaction check failed: %1%") % p);
         }
       }
     }
diff --git a/src/times.cc b/src/times.cc
index 30da301f..6bf2af82 100644
--- a/src/times.cc
+++ b/src/times.cc
@@ -230,7 +230,7 @@ namespace {
         if (! *p || *p != *q) break;
       }
       if (*p != '\0' || *q != '\0')
-        throw_(date_error, _("Invalid date: %1") << date_str);
+        throw_(date_error, _f("Invalid date: %1%") % date_str);
 
       if (traits)
         *traits = io.traits;
@@ -260,7 +260,7 @@ namespace {
         return when;
     }
 
-    throw_(date_error, _("Invalid date: %1") << date_str);
+    throw_(date_error, _f("Invalid date: %1%") % date_str);
     return date_t();
   }
 }
@@ -329,7 +329,7 @@ datetime_t parse_datetime(const char * str)
   if (when.is_not_a_date_time()) {
     when = timelog_datetime_io->parse(buf);
     if (when.is_not_a_date_time()) {
-      throw_(date_error, _("Invalid date/time: %1") << str);
+      throw_(date_error, _f("Invalid date/time: %1%") % str);
     }
   }
   return when;
@@ -1682,7 +1682,7 @@ void date_parser_t::lexer_t::token_t::unexpected()
   default: {
     string desc = to_string();
     kind = UNKNOWN;
-    throw_(date_error, _("Unexpected date period token '%1'") << desc);
+    throw_(date_error, _f("Unexpected date period token '%1%'") % desc);
   }
   }
 }
@@ -1693,12 +1693,12 @@ void date_parser_t::lexer_t::token_t::expected(char wanted, char c)
     if (wanted == '\0' || wanted == -1)
       throw_(date_error, _("Unexpected end"));
     else
-      throw_(date_error, _("Missing '%1'") << wanted);
+      throw_(date_error, _f("Missing '%1%'") % wanted);
   } else {
     if (wanted == '\0' || wanted == -1)
-      throw_(date_error, _("Invalid char '%1'") << c);
+      throw_(date_error, _f("Invalid char '%1%'") % c);
     else
-      throw_(date_error, _("Invalid char '%1' (wanted '%2')") << c << wanted);
+      throw_(date_error, _f("Invalid char '%1%' (wanted '%2%')") % c % wanted);
   }
 }
 
diff --git a/src/token.cc b/src/token.cc
index 1392c29f..1c43af32 100644
--- a/src/token.cc
+++ b/src/token.cc
@@ -479,26 +479,26 @@ void expr_t::token_t::unexpected(const char wanted)
     case TOK_EOF:
       throw_(parse_error, _("Unexpected end of expression"));
     case IDENT:
-      throw_(parse_error, _("Unexpected symbol '%1'") << value);
+      throw_(parse_error, _f("Unexpected symbol '%1%'") % value);
     case VALUE:
-      throw_(parse_error, _("Unexpected value '%1'") << value);
+      throw_(parse_error, _f("Unexpected value '%1%'") % value);
     default:
-      throw_(parse_error, _("Unexpected expression token '%1'") << symbol);
+      throw_(parse_error, _f("Unexpected expression token '%1%'") % symbol);
     }
   } else {
     switch (prev_kind) {
     case TOK_EOF:
       throw_(parse_error,
-             _("Unexpected end of expression (wanted '%1')") << wanted);
+             _f("Unexpected end of expression (wanted '%1%')") % wanted);
     case IDENT:
       throw_(parse_error,
-             _("Unexpected symbol '%1' (wanted '%2')") << value << wanted);
+             _f("Unexpected symbol '%1%' (wanted '%2%')") % value % wanted);
     case VALUE:
       throw_(parse_error,
-             _("Unexpected value '%1' (wanted '%2')") << value << wanted);
+             _f("Unexpected value '%1%' (wanted '%2%')") % value % wanted);
     default:
-      throw_(parse_error, _("Unexpected expression token '%1' (wanted '%2')")
-             << symbol << wanted);
+      throw_(parse_error, _f("Unexpected expression token '%1%' (wanted '%2%')")
+             % symbol % wanted);
     }
   }
 }
@@ -509,13 +509,13 @@ void expr_t::token_t::expected(const char wanted, char c)
     if (wanted == '\0' || wanted == -1)
       throw_(parse_error, _("Unexpected end"));
     else
-      throw_(parse_error, _("Missing '%1'") << wanted);
+      throw_(parse_error, _f("Missing '%1%'") % wanted);
   } else {
     if (wanted == '\0' || wanted == -1)
-      throw_(parse_error, _("Invalid char '%1'") << c);
+      throw_(parse_error, _f("Invalid char '%1%'") % c);
     else
       throw_(parse_error,
-             _("Invalid char '%1' (wanted '%2')") << c << wanted);
+             _f("Invalid char '%1%' (wanted '%2%')") % c % wanted);
   }
 }
 
@@ -523,10 +523,10 @@ void expr_t::token_t::expected(const kind_t wanted)
 {
   try {
     if (wanted == '\0' || wanted == -1)
-      throw_(parse_error, _("Invalid token '%1'") << *this);
+      throw_(parse_error, _f("Invalid token '%1%'") % *this);
     else
       throw_(parse_error,
-             _("Invalid token '%1' (wanted '%2')") << *this << wanted);
+             _f("Invalid token '%1%' (wanted '%2%')") % *this % wanted);
   }
   catch (...) {
     kind = ERROR;
diff --git a/src/utils.cc b/src/utils.cc
index ada6b600..d8cba61e 100644
--- a/src/utils.cc
+++ b/src/utils.cc
@@ -393,7 +393,7 @@ void trace_dtor_func(void * ptr, const char * cls_name, std::size_t cls_size)
 
   objects_map::iterator i = live_objects->find(ptr);
   if (i == live_objects->end()) {
-    warning_(_("Attempting to delete %1 a non-living %2") << ptr << cls_name);
+    warning_(_f("Attempting to delete %1% a non-living %2%") % ptr % cls_name);
     memory_tracing_active = true;
     return;
   }
@@ -408,7 +408,7 @@ void trace_dtor_func(void * ptr, const char * cls_name, std::size_t cls_size)
 
   object_count_map::iterator k = live_object_count->find(cls_name);
   if (k == live_object_count->end()) {
-    warning_(_("Failed to find %1 in live object counts") << cls_name);
+    warning_(_f("Failed to find %1% in live object counts") % cls_name);
     memory_tracing_active = true;
     return;
   }
@@ -572,7 +572,7 @@ strings_list split_arguments(const char * line)
 
   if (in_quoted_string)
     throw_(std::logic_error,
-           _("Unterminated string, expected '%1'") << in_quoted_string);
+           _f("Unterminated string, expected '%1%'") % in_quoted_string);
 
   if (q != buf) {
     *q = '\0';
diff --git a/src/value.cc b/src/value.cc
index 2b1b561f..b475b6a2 100644
--- a/src/value.cc
+++ b/src/value.cc
@@ -103,8 +103,8 @@ value_t::operator bool() const
     std::ostringstream out;
     out << *this;
     throw_(value_error,
-           _("Cannot determine truth of %1 (did you mean 'account =~ %2'?)")
-           << label() << out.str());
+           _f("Cannot determine truth of %1% (did you mean 'account =~ %2%'?)")
+           % label() % out.str());
   }
   case SEQUENCE:
     if (! as_sequence().empty()) {
@@ -120,8 +120,8 @@ value_t::operator bool() const
     return ! as_any().empty();
   }
 
-  add_error_context(_("While taking boolean value of %1:") << *this);
-  throw_(value_error, _("Cannot determine truth of %1") << label());
+  add_error_context(_f("While taking boolean value of %1%:") % *this);
+  throw_(value_error, _f("Cannot determine truth of %1%") % label());
 
   return false;
 }
@@ -307,8 +307,8 @@ value_t value_t::number() const
     break;
   }
 
-  add_error_context(_("While calling number() on %1:") << *this);
-  throw_(value_error, _("Cannot determine numeric value of %1") << label());
+  add_error_context(_f("While calling number() on %1%:") % *this);
+  throw_(value_error, _f("Cannot determine numeric value of %1%") % label());
 
   return false;
 }
@@ -331,7 +331,7 @@ value_t& value_t::operator+=(const value_t& val)
         for (; i != end(); i++, j++)
           *i += *j;
       } else {
-        add_error_context(_("While adding %1 to %2:") << val << *this);
+        add_error_context(_f("While adding %1% to %2%:") % val % *this);
         throw_(value_error, _("Cannot add sequences of different lengths"));
       }
     } else {
@@ -442,8 +442,8 @@ value_t& value_t::operator+=(const value_t& val)
     break;
   }
 
-  add_error_context(_("While adding %1 to %2:") << val << *this);
-  throw_(value_error, _("Cannot add %1 to %2") << val.label() << label());
+  add_error_context(_f("While adding %1% to %2%:") % val % *this);
+  throw_(value_error, _f("Cannot add %1% to %2%") % val.label() % label());
 
   return *this;
 }
@@ -461,7 +461,7 @@ value_t& value_t::operator-=(const value_t& val)
         for (; i != end(); i++, j++)
           *i -= *j;
       } else {
-        add_error_context(_("While subtracting %1 from %2:") << val << *this);
+        add_error_context(_f("While subtracting %1% from %2%:") % val % *this);
         throw_(value_error, _("Cannot subtract sequences of different lengths"));
       }
     } else {
@@ -582,8 +582,8 @@ value_t& value_t::operator-=(const value_t& val)
     break;
   }
 
-  add_error_context(_("While subtracting %1 from %2:") << val << *this);
-  throw_(value_error, _("Cannot subtract %1 from %2") << val.label() << label());
+  add_error_context(_f("While subtracting %1% from %2%:") % val % *this);
+  throw_(value_error, _f("Cannot subtract %1% from %2%") % val.label() % label());
 
   return *this;
 }
@@ -664,8 +664,8 @@ value_t& value_t::operator*=(const value_t& val)
     break;
   }
 
-  add_error_context(_("While multiplying %1 with %2:") << val << *this);
-  throw_(value_error, _("Cannot multiply %1 with %2") << label() << val.label());
+  add_error_context(_f("While multiplying %1% with %2%:") % val % *this);
+  throw_(value_error, _f("Cannot multiply %1% with %2%") % label() % val.label());
 
   return *this;
 }
@@ -742,8 +742,8 @@ value_t& value_t::operator/=(const value_t& val)
     break;
   }
 
-  add_error_context(_("While dividing %1 by %2:") << *this << val);
-  throw_(value_error, _("Cannot divide %1 by %2") << label() << val.label());
+  add_error_context(_f("While dividing %1% by %2%:") % *this % val);
+  throw_(value_error, _f("Cannot divide %1% by %2%") % label() % val.label());
 
   return *this;
 }
@@ -828,8 +828,8 @@ bool value_t::is_equal_to(const value_t& val) const
     break;
   }
 
-  add_error_context(_("While comparing equality of %1 and %2:") << *this << val);
-  throw_(value_error, _("Cannot compare %1 to %2") << label() << val.label());
+  add_error_context(_f("While comparing equality of %1% and %2%:") % *this % val);
+  throw_(value_error, _f("Cannot compare %1% to %2%") % label() % val.label());
 
   return *this;
 }
@@ -948,8 +948,8 @@ bool value_t::is_less_than(const value_t& val) const
     break;
   }
 
-  add_error_context(_("While comparing if %1 is less than %2:") << *this << val);
-  throw_(value_error, _("Cannot compare %1 to %2") << label() << val.label());
+  add_error_context(_f("While comparing if %1% is less than %2%:") % *this % val);
+  throw_(value_error, _f("Cannot compare %1% to %2%") % label() % val.label());
 
   return *this;
 }
@@ -1063,8 +1063,8 @@ bool value_t::is_greater_than(const value_t& val) const
     break;
   }
 
-  add_error_context(_("While comparing if %1 is greater than %2:") << *this << val);
-  throw_(value_error, _("Cannot compare %1 to %2") << label() << val.label());
+  add_error_context(_f("While comparing if %1% is greater than %2%:") % *this % val);
+  throw_(value_error, _f("Cannot compare %1% to %2%") % label() % val.label());
 
   return *this;
 }
@@ -1205,9 +1205,9 @@ void value_t::in_place_cast(type_t cast_type)
         return;
       }
       else {
-        add_error_context(_("While converting %1 to an amount:") << *this);
-        throw_(value_error, _("Cannot convert %1 with multiple commodities to %2")
-               << label() << label(cast_type));
+        add_error_context(_f("While converting %1% to an amount:") % *this);
+        throw_(value_error, _f("Cannot convert %1% with multiple commodities to %2%")
+               % label() % label(cast_type));
       }
       break;
     }
@@ -1263,9 +1263,9 @@ void value_t::in_place_cast(type_t cast_type)
     break;
   }
 
-  add_error_context(_("While converting %1:") << *this);
+  add_error_context(_f("While converting %1%:") % *this);
   throw_(value_error,
-         _("Cannot convert %1 to %2") << label() << label(cast_type));
+         _f("Cannot convert %1% to %2%") % label() % label(cast_type));
 }
 
 void value_t::in_place_negate()
@@ -1295,8 +1295,8 @@ void value_t::in_place_negate()
     break;
   }
 
-  add_error_context(_("While negating %1:") << *this);
-  throw_(value_error, _("Cannot negate %1") << label());
+  add_error_context(_f("While negating %1%:") % *this);
+  throw_(value_error, _f("Cannot negate %1%") % label());
 }
 
 void value_t::in_place_not()
@@ -1329,8 +1329,8 @@ void value_t::in_place_not()
     break;
   }
 
-  add_error_context(_("While applying not to %1:") << *this);
-  throw_(value_error, _("Cannot 'not' %1") << label());
+  add_error_context(_f("While applying not to %1%:") % *this);
+  throw_(value_error, _f("Cannot 'not' %1%") % label());
 }
 
 bool value_t::is_realzero() const
@@ -1359,8 +1359,8 @@ bool value_t::is_realzero() const
     return as_any().empty();
 
   default:
-    add_error_context(_("While applying is_realzero to %1:") << *this);
-    throw_(value_error, _("Cannot determine if %1 is really zero") << label());
+    add_error_context(_f("While applying is_realzero to %1%:") % *this);
+    throw_(value_error, _f("Cannot determine if %1% is really zero") % label());
   }
   return false;
 }
@@ -1391,8 +1391,8 @@ bool value_t::is_zero() const
     return as_any().empty();
 
   default:
-    add_error_context(_("While applying is_zero to %1:") << *this);
-    throw_(value_error, _("Cannot determine if %1 is zero") << label());
+    add_error_context(_f("While applying is_zero to %1%:") % *this);
+    throw_(value_error, _f("Cannot determine if %1% is zero") % label());
   }
   return false;
 }
@@ -1425,8 +1425,8 @@ value_t value_t::value(const datetime_t&   moment,
     break;
   }
 
-  add_error_context(_("While finding valuation of %1:") << *this);
-  throw_(value_error, _("Cannot find the value of %1") << label());
+  add_error_context(_f("While finding valuation of %1%:") % *this);
+  throw_(value_error, _f("Cannot find the value of %1%") % label());
   return NULL_VALUE;
 }
 
@@ -1544,7 +1544,7 @@ void value_t::in_place_reduce()
     return;
   }
 
-  //throw_(value_error, "Cannot reduce " << label());
+  //throw_(value_error, _f("Cannot reduce %1%") % label());
 }
 
 void value_t::in_place_unreduce()
@@ -1564,7 +1564,7 @@ void value_t::in_place_unreduce()
     return;
   }
 
-  //throw_(value_error, "Cannot reduce " << label());
+  //throw_(value_error, _f("Cannot reduce %1%") % label());
 }
 
 value_t value_t::abs() const
@@ -1584,8 +1584,8 @@ value_t value_t::abs() const
     break;
   }
 
-  add_error_context(_("While taking abs of %1:") << *this);
-  throw_(value_error, _("Cannot abs %1") << label());
+  add_error_context(_f("While taking abs of %1%:") % *this);
+  throw_(value_error, _f("Cannot abs %1%") % label());
   return NULL_VALUE;
 }
 
@@ -1608,8 +1608,8 @@ void value_t::in_place_round()
     break;
   }
 
-  add_error_context(_("While rounding %1:") << *this);
-  throw_(value_error, _("Cannot set rounding for %1") << label());
+  add_error_context(_f("While rounding %1%:") % *this);
+  throw_(value_error, _f("Cannot set rounding for %1%") % label());
 }
 
 void value_t::in_place_truncate()
@@ -1631,8 +1631,8 @@ void value_t::in_place_truncate()
     break;
   }
 
-  add_error_context(_("While truncating %1:") << *this);
-  throw_(value_error, _("Cannot truncate %1") << label());
+  add_error_context(_f("While truncating %1%:") % *this);
+  throw_(value_error, _f("Cannot truncate %1%") % label());
 }
 
 void value_t::in_place_floor()
@@ -1654,8 +1654,8 @@ void value_t::in_place_floor()
     break;
   }
 
-  add_error_context(_("While flooring %1:") << *this);
-  throw_(value_error, _("Cannot floor %1") << label());
+  add_error_context(_f("While flooring %1%:") % *this);
+  throw_(value_error, _f("Cannot floor %1%") % label());
 }
 
 void value_t::in_place_unround()
@@ -1677,8 +1677,8 @@ void value_t::in_place_unround()
     break;
   }
 
-  add_error_context(_("While unrounding %1:") << *this);
-  throw_(value_error, _("Cannot unround %1") << label());
+  add_error_context(_f("While unrounding %1%:") % *this);
+  throw_(value_error, _f("Cannot unround %1%") % label());
 }
 
 void value_t::annotate(const annotation_t& details)
@@ -1686,8 +1686,8 @@ void value_t::annotate(const annotation_t& details)
   if (is_amount()) {
     as_amount_lval().annotate(details);
   } else {
-    add_error_context(_("While attempting to annotate %1:") << *this);
-    throw_(value_error, _("Cannot annotate %1") << label());
+    add_error_context(_f("While attempting to annotate %1%:") % *this);
+    throw_(value_error, _f("Cannot annotate %1%") % label());
   }
 }
 
@@ -1696,9 +1696,9 @@ bool value_t::has_annotation() const
   if (is_amount()) {
     return as_amount().has_annotation();
   } else {
-    add_error_context(_("While checking if %1 has annotations:") << *this);
+    add_error_context(_f("While checking if %1% has annotations:") % *this);
     throw_(value_error,
-           _("Cannot determine whether %1 is annotated") << label());
+           _f("Cannot determine whether %1% is annotated") % label());
   }
   return false;
 }
@@ -1708,8 +1708,8 @@ annotation_t& value_t::annotation()
   if (is_amount()) {
     return as_amount_lval().annotation();
   } else {
-    add_error_context(_("While requesting the annotations of %1:") << *this);
-    throw_(value_error, _("Cannot request annotation of %1") << label());
+    add_error_context(_f("While requesting the annotations of %1%:") % *this);
+    throw_(value_error, _f("Cannot request annotation of %1%") % label());
     return as_amount_lval().annotation(); // quiet g++ warning
   }
 }
diff --git a/src/xact.cc b/src/xact.cc
index 226fd5ab..07ca7911 100644
--- a/src/xact.cc
+++ b/src/xact.cc
@@ -184,8 +184,8 @@ bool xact_base_t::finalize()
 
       if (post_account_bad || null_post_account_bad)
         throw_(std::logic_error,
-               _("Posting with null amount's account may be mispelled:\n  \"%1\"")
-               << (post_account_bad ? post->account->fullname() :
+               _f("Posting with null amount's account may be mispelled:\n  \"%1%\"")
+               % (post_account_bad ? post->account->fullname() :
                    null_post->account->fullname()));
       else
         throw_(std::logic_error,
@@ -706,10 +706,9 @@ void auto_xact_t::extend_xact(xact_base_t& xact, parse_context_t& context)
           else if (! pair.first.calc(bound_scope).to_boolean()) {
             if (pair.second == expr_t::EXPR_ASSERTION)
               throw_(parse_error,
-                     _("Transaction assertion failed: %1") << pair.first);
+                     _f("Transaction assertion failed: %1%") % pair.first);
             else
-              context.warning(STR(_("Transaction check failed: %1")
-                                  << pair.first));
+              context.warning(_f("Transaction check failed: %1%") % pair.first);
           }
         }
       }
diff --git a/src/xact.h b/src/xact.h
index 59430285..873c1a9e 100644
--- a/src/xact.h
+++ b/src/xact.h
@@ -129,7 +129,7 @@ public:
   virtual string description() {
     if (pos) {
       std::ostringstream buf;
-      buf << _("transaction at line %1") << pos->beg_line;
+      buf << _f("transaction at line %1") << pos->beg_line;
       return buf.str();
     } else {
       return string(_("generated transaction"));
@@ -220,7 +220,7 @@ private:
   virtual string description() {
     if (pos) {
       std::ostringstream buf;
-      buf << _("automated transaction at line %1") << pos->beg_line;
+      buf << _f("automated transaction at line %1") << pos->beg_line;
       return buf.str();
     } else {
       return string(_("generated automated transaction"));
@@ -278,7 +278,7 @@ class period_xact_t : public xact_base_t
   virtual string description() {
     if (pos) {
       std::ostringstream buf;
-      buf << _("periodic transaction at line %1") << pos->beg_line;
+      buf << _f("periodic transaction at line %1") << pos->beg_line;
       return buf.str();
     } else {
       return string(_("generated periodic transaction"));