[glibmm] Derive Glib::Error from std::exception, remove Glib::Exception

[Kjell Ahlstedt <kjellahl src gnome org>]

commit 2f4a122fa05e9e6514f62112d75d1ee7e4d894f2
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Sat Dec 14 12:31:39 2019 +0100

    Derive Glib::Error from std::exception, remove Glib::Exception
    
    Glib::Error::what() returns const char* (was Glib::ustring). It overrides
    std::exception::what() that returns const char* and is noexcept.
    Fixes #23

 glib/glibmm.h                         |  1 -
 glib/glibmm/error.cc                  |  6 +++---
 glib/glibmm/error.h                   |  6 +++---
 glib/glibmm/exception.cc              | 39 -----------------------------------
 glib/glibmm/exception.h               | 36 --------------------------------
 glib/glibmm/filelist.am               |  2 --
 tests/giomm_ioerror/main.cc           |  4 ++--
 tests/giomm_memoryinputstream/main.cc |  2 +-
 tests/giomm_simple/main.cc            |  2 +-
 9 files changed, 10 insertions(+), 88 deletions(-)
---
diff --git a/glib/glibmm.h b/glib/glibmm.h
index a7587d17..93e3a4ff 100644
--- a/glib/glibmm.h
+++ b/glib/glibmm.h
@@ -99,7 +99,6 @@
 #include <glibmm/dispatcher.h>
 #include <glibmm/enums.h>
 #include <glibmm/error.h>
-#include <glibmm/exception.h>
 #include <glibmm/exceptionhandler.h>
 #include <glibmm/fileutils.h>
 #include <glibmm/interface.h>
diff --git a/glib/glibmm/error.cc b/glib/glibmm/error.cc
index 68c20e18..c8e22fc3 100644
--- a/glib/glibmm/error.cc
+++ b/glib/glibmm/error.cc
@@ -50,7 +50,7 @@ Error::Error(GError* gobject, bool take_copy)
 }
 
 Error::Error(const Error& other)
-: Exception(other), gobject_((other.gobject_) ? g_error_copy(other.gobject_) : nullptr)
+: std::exception(other), gobject_((other.gobject_) ? g_error_copy(other.gobject_) : nullptr)
 {
 }
 
@@ -99,8 +99,8 @@ Error::code() const
   return gobject_->code;
 }
 
-Glib::ustring
-Error::what() const
+const char*
+Error::what() const noexcept
 {
   g_return_val_if_fail(gobject_ != nullptr, "");
   g_return_val_if_fail(gobject_->message != nullptr, "");
diff --git a/glib/glibmm/error.h b/glib/glibmm/error.h
index 5f49ee26..32e3a60c 100644
--- a/glib/glibmm/error.h
+++ b/glib/glibmm/error.h
@@ -18,14 +18,14 @@
  */
 
 #include <glibmmconfig.h>
-#include <glibmm/exception.h>
 #include <glibmm/value.h>
 #include <glib.h>
+#include <exception>
 
 namespace Glib
 {
 
-class Error : public Glib::Exception
+class Error : public std::exception
 {
 public:
   Error();
@@ -45,7 +45,7 @@ public:
 
   GQuark domain() const;
   int code() const;
-  Glib::ustring what() const override;
+  const char* what() const noexcept override;
 
   bool matches(GQuark error_domain, int error_code) const;
 
diff --git a/glib/glibmm/filelist.am b/glib/glibmm/filelist.am
index 530c439f..e606d5fd 100644
--- a/glib/glibmm/filelist.am
+++ b/glib/glibmm/filelist.am
@@ -9,7 +9,6 @@ glibmm_files_extra_cc =                 \
        debug.cc                        \
        dispatcher.cc                   \
        error.cc                        \
-       exception.cc                    \
        exceptionhandler.cc             \
        extraclassinit.cc               \
        init.cc                         \
@@ -42,7 +41,6 @@ glibmm_files_extra_h =                        \
        debug.h                         \
        dispatcher.h                    \
        error.h                         \
-       exception.h                     \
        exceptionhandler.h              \
        extraclassinit.h                \
        i18n-lib.h                      \
diff --git a/tests/giomm_ioerror/main.cc b/tests/giomm_ioerror/main.cc
index 8aaa4298..de312f8a 100644
--- a/tests/giomm_ioerror/main.cc
+++ b/tests/giomm_ioerror/main.cc
@@ -73,9 +73,9 @@ main(int, char**)
     else
       std::cerr << "Gio::Error exception caught: " << ex.what() << std::endl;
   }
-  catch (const Glib::Exception& ex)
+  catch (const Glib::Error& ex)
   {
-    std::cerr << "Exception caught: " << ex.what() << std::endl;
+    std::cerr << "Glib::Error exception caught: " << ex.what() << std::endl;
     return EXIT_FAILURE;
   }
 
diff --git a/tests/giomm_memoryinputstream/main.cc b/tests/giomm_memoryinputstream/main.cc
index ce1b54ec..cbf682fb 100644
--- a/tests/giomm_memoryinputstream/main.cc
+++ b/tests/giomm_memoryinputstream/main.cc
@@ -77,7 +77,7 @@ main(int, char**)
       return EXIT_FAILURE;
     }
   }
-  catch (const Glib::Exception& ex)
+  catch (const Glib::Error& ex)
   {
     std::cerr << "Exception caught: " << ex.what() << std::endl;
     return EXIT_FAILURE;
diff --git a/tests/giomm_simple/main.cc b/tests/giomm_simple/main.cc
index 7b1e8767..0a73cb51 100644
--- a/tests/giomm_simple/main.cc
+++ b/tests/giomm_simple/main.cc
@@ -49,7 +49,7 @@ main(int, char**)
       return EXIT_FAILURE;
     }
   }
-  catch (const Glib::Exception& ex)
+  catch (const Glib::Error& ex)
   {
     std::cerr << "Exception caught: " << ex.what() << std::endl;
     return EXIT_FAILURE;