# HG changeset patch
# User jbe
# Date 1406509240 -7200
# Node ID 663722e35330f2360bcbdb5f1307824793709908
# Parent  a1507b499fa52bbfc93fee42c0a212d44326c387
Added pairs metamethod for (sparse) JSON objects

diff -r a1507b499fa5 -r 663722e35330 libraries/json/json.c
--- a/libraries/json/json.c	Sun Jul 27 22:42:52 2014 +0200
+++ b/libraries/json/json.c	Mon Jul 28 03:00:40 2014 +0200
@@ -7,7 +7,8 @@
 #define JSON_UPVAL_SHADOWTBL lua_upvalueindex(2)
 #define JSON_UPVAL_TYPES     lua_upvalueindex(3)
 #define JSON_UPVAL_METATABLE lua_upvalueindex(4)
-#define JSON_UPVAL_IPAIRS_ITERFUNC lua_upvalueindex(5)
+#define JSON_UPVAL_PAIRS_ITERFUNC  lua_upvalueindex(5)
+#define JSON_UPVAL_IPAIRS_ITERFUNC lua_upvalueindex(6)
 
 #define JSON_STATE_VALUE 0
 #define JSON_STATE_OBJECT_KEY 1
@@ -355,6 +356,27 @@
   return 1;
 }
 
+static int json_pairs_iterfunc(lua_State *L) {
+  lua_settop(L, 2);
+  lua_pushvalue(L, 1);
+  lua_rawget(L, JSON_UPVAL_SHADOWTBL);
+  if (lua_isnil(L, -1)) return luaL_error(L, "Shadow table not found");
+  lua_pushvalue(L, 2);
+  if (!lua_next(L, -2)) return 0;
+  if (lua_rawequal(L, -1, JSON_UPVAL_NULLMARK)) {
+    lua_pop(L, 1);
+    lua_pushnil(L);
+  }
+  return 2;
+}
+
+static int json_pairs(lua_State *L) {
+  lua_pushvalue(L, JSON_UPVAL_PAIRS_ITERFUNC);
+  lua_pushvalue(L, 1);
+  lua_pushnil(L);
+  return 3;
+}
+
 static int json_ipairs_iterfunc(lua_State *L) {
   int idx;
   lua_settop(L, 2);
@@ -392,6 +414,7 @@
   {"__len", json_len},
   {"__index", json_index},
   {"__newindex", json_newindex},
+  {"__pairs", json_pairs},
   {"__ipairs", json_ipairs},
   {NULL, NULL}
 };
@@ -410,21 +433,25 @@
   lua_setmetatable(L, 3);
   lua_setmetatable(L, 4);
   lua_newtable(L);  // 5: metatable for JSON objects and JSON arrays
-  lua_pushvalue(L, 5);
-  lua_setfield(L, 1, "metatable");
   lua_pushvalue(L, 2);
   lua_pushvalue(L, 3);
   lua_pushvalue(L, 4);
   lua_pushvalue(L, 5);
-  lua_pushcclosure(L, json_ipairs_iterfunc, 4);  // 6: iteration function for ipairs
+  lua_pushcclosure(L, json_pairs_iterfunc, 4);  // 6: iteration function for pairs
+  lua_pushvalue(L, 2);
+  lua_pushvalue(L, 3);
+  lua_pushvalue(L, 4);
+  lua_pushvalue(L, 5);
+  lua_pushcclosure(L, json_ipairs_iterfunc, 4);  // 7: iteration function for ipairs
   lua_pushvalue(L, 5);
   lua_pushvalue(L, 2);
   lua_pushvalue(L, 3);
   lua_pushvalue(L, 4);
   lua_pushvalue(L, 5);
   lua_pushvalue(L, 6);
-  luaL_setfuncs(L, json_metatable_functions, 5);
-  lua_pop(L, 1);
-  luaL_setfuncs(L, json_module_functions, 5);
+  lua_pushvalue(L, 7);
+  luaL_setfuncs(L, json_metatable_functions, 6);
+  lua_setfield(L, 1, "metatable");
+  luaL_setfuncs(L, json_module_functions, 6);
   return 1;
 }