Lua 5.3.0-beta5.3.0-beta

1 files changed, 21 insertions, 22 deletions

diff --git a/src/lua.c b/src/lua.c
index f46f9fb3..b23bb005 100644
--- a/src/lua.c
+++ b/src/lua.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lua.c,v 1.213 2014/06/30 19:48:08 roberto Exp $
+** $Id: lua.c,v 1.217 2014/10/20 22:21:05 roberto Exp $
 ** Lua stand-alone interpreter
 ** See Copyright Notice in lua.h
 */
@@ -134,9 +134,9 @@ static void print_usage (const char *badoption) {
   luai_writestringerror(
   "usage: %s [options] [script [args]]\n"
   "Available options are:\n"
-  "  -e stat  execute string " LUA_QL("stat") "\n"
-  "  -i       enter interactive mode after executing " LUA_QL("script") "\n"
-  "  -l name  require library " LUA_QL("name") "\n"
+  "  -e stat  execute string 'stat'\n"
+  "  -i       enter interactive mode after executing 'script'\n"
+  "  -l name  require library 'name'\n"
   "  -v       show version information\n"
   "  -E       ignore environment variables\n"
   "  --       stop handling options\n"
@@ -158,34 +158,34 @@ static void l_message (const char *pname, const char *msg) {
 
 /*
 ** Check whether 'status' is not OK and, if so, prints the error
-** message on the top of the stack. Because this function can be called
-** unprotected, it only accepts actual strings as error messages. (A
-** coercion could raise a memory error.)
+** message on the top of the stack. It assumes that the error object
+** is a string, as it was either generated by Lua or by 'msghandler'.
 */
 static int report (lua_State *L, int status) {
   if (status != LUA_OK) {
-    const char *msg = (lua_type(L, -1) == LUA_TSTRING) ? lua_tostring(L, -1)
-                                                       : NULL;
-    if (msg == NULL) msg = "(error object is not a string)";
+    const char *msg = lua_tostring(L, -1);
     l_message(progname, msg);
-    lua_pop(L, 1);
+    lua_pop(L, 1);  /* remove message */
   }
   return status;
 }
 
 
 /*
-** Message handler to be used to run all chunks
+** Message handler used to run all chunks
 */
 static int msghandler (lua_State *L) {
   const char *msg = lua_tostring(L, 1);
-  if (msg)  /* is error object a string? */
-    luaL_traceback(L, L, msg, 1);  /* use standard traceback */
-  else if (!lua_isnoneornil(L, 1)) {  /* non-string error object? */
-    if (!luaL_callmeta(L, 1, "__tostring"))  /* try its 'tostring' metamethod */
-      lua_pushliteral(L, "(no error message)");
-  }  /* else no error object, does nothing */
-  return 1;
+  if (msg == NULL) {  /* is error object not a string? */
+    if (luaL_callmeta(L, 1, "__tostring") &&  /* does it have a metamethod */
+        lua_type(L, -1) == LUA_TSTRING)  /* that produces a string? */
+      return 1;  /* that is the message */
+    else
+      msg = lua_pushfstring(L, "(error object is a %s value)",
+                               luaL_typename(L, 1));
+  }
+  luaL_traceback(L, L, msg, 1);  /* append a standard traceback */
+  return 1;  /* return the traceback */
 }
 
 
@@ -389,9 +389,8 @@ static void l_print (lua_State *L) {
     lua_getglobal(L, "print");
     lua_insert(L, 1);
     if (lua_pcall(L, n, 0, 0) != LUA_OK)
-      l_message(progname, lua_pushfstring(L,
-                             "error calling " LUA_QL("print") " (%s)",
-                             lua_tostring(L, -1)));
+      l_message(progname, lua_pushfstring(L, "error calling 'print' (%s)",
+                                             lua_tostring(L, -1)));
   }
 }