From 8b97caae46ef60091de5bb29681b0fa31439c082 Mon Sep 17 00:00:00 2001
From: Dave Abrahams <dave@boostpro.com>
Date: Thu, 11 Sep 2003 15:09:11 +0000
Subject: [PATCH] Warn about duplicate to-python converters and show the name
 of the offending type.

[SVN r20023]
---
 doc/news.html              |  8 +++++++-
 src/converter/registry.cpp | 13 +++++++++++--
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/doc/news.html b/doc/news.html
index 3b38951a..19b00ecb 100644
--- a/doc/news.html
+++ b/doc/news.html
@@ -29,6 +29,12 @@
     <hr>
 
     <dl class="page-index">
+      <dt>11 Sept 2003</dt>
+
+      <dd>Changed the response to multiple to-python converters being
+      registered for the same type from a hard error into warning;
+      Boost.Python now reports the offending type in the message.
+
       <dt>9 Sept 2003</dt>
 
       <dd>Added new <code><a
@@ -164,7 +170,7 @@ BOOST_PYTHON_MODULE(test)
 
     <p>Revised 
     <!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
-     1 August 2003 <!--webbot bot="Timestamp" endspan i-checksum="39359" -->
+     11 September 2003 <!--webbot bot="Timestamp" endspan i-checksum="39359" -->
     </p>
 
     <p><i>&copy; Copyright <a href="../../../people/dave_abrahams.htm">Dave
diff --git a/src/converter/registry.cpp b/src/converter/registry.cpp
index 2e747a14..ce12ec81 100644
--- a/src/converter/registry.cpp
+++ b/src/converter/registry.cpp
@@ -9,6 +9,7 @@
 
 #include <set>
 #include <stdexcept>
+#include <boost/lexical_cast.hpp>
 
 #if defined(__APPLE__) && defined(__MACH__) && defined(__GNUC__) \
  && __GNUC__ == 3 && __GNUC_MINOR__ == 3 && !defined(__APPLE_CC__)
@@ -161,8 +162,16 @@ namespace registry
       assert(slot == 0); // we have a problem otherwise
       if (slot != 0)
       {
-          throw std::runtime_error(
-              "trying to register to_python_converter for a type which already has a registered to_python_converter");
+          std::string msg(
+              "to-Python converter for "
+              + lexical_cast<std::string>(source_t)
+              + " already registered; second conversion method ignored."
+          );
+          
+          if ( ::PyErr_Warn( NULL, const_cast<char*>(msg.c_str()) ) )
+          {
+              throw_error_already_set();
+          }
       }
       slot = f;
   }