From 7078d1243d795855cca7b1f825a8e5fbaf3e3350 Mon Sep 17 00:00:00 2001
From: jyelon <jyelon@gmail.com>
Date: Thu, 13 Apr 2023 14:55:21 -0400
Subject: [PATCH] LuaExtraArgs is now fully implemented, efficiently

---
 luprex/Makefile              |  3 +++
 luprex/cpp/core/luastack.hpp | 48 ++++++++++--------------------------
 2 files changed, 16 insertions(+), 35 deletions(-)

diff --git a/luprex/Makefile b/luprex/Makefile
index a4412cb2..ea27acf4 100644
--- a/luprex/Makefile
+++ b/luprex/Makefile
@@ -139,6 +139,9 @@ obj/eris/%.o: ext/eris-master/src/%.c
 obj/core/%.o: cpp/core/%.cpp
 	$(GPP) -fPIC -I./ext/eris-master/src -I./cpp/wrap -I./cpp/core -o $@ -c $<
 
+obj/core/%.s: cpp/core/%.cpp
+	$(GPP) -S -fPIC -I./ext/eris-master/src -I./cpp/wrap -I./cpp/core -o $@ -c $<
+
 obj/drv/%.o: cpp/drv/%.cpp
 	$(GPP) -I./ext -I./src/drv -o $@ -c $<
 
diff --git a/luprex/cpp/core/luastack.hpp b/luprex/cpp/core/luastack.hpp
index 1d9dda3a..df11b2e3 100644
--- a/luprex/cpp/core/luastack.hpp
+++ b/luprex/cpp/core/luastack.hpp
@@ -667,33 +667,8 @@ public:
 
 class LuaDefStack : public LuaCoreStack {
 private:
-    int top_;
     int nret_;
 
-    template<int RETP, int ARGP, int VARP, int EXTRAP, int EXTRAC, class... SS>
-    void assign_slots(LuaRet &v, SS & ... stackslots) {
-        v.index_ = RETP;
-        assign_slots<RETP+1, ARGP, VARP, EXTRAP, EXTRAC>(stackslots...);
-    }
-    template<int RETP, int ARGP, int VARP, int EXTRAP, int EXTRAC, class... SS>
-    void assign_slots(LuaArg &v, SS & ... stackslots) {
-        v.index_ = ARGP;
-        assign_slots<RETP, ARGP+1, VARP, EXTRAP, EXTRAC>(stackslots...);
-    }
-    template<int RETP, int ARGP, int VARP, int EXTRAP, int EXTRAC, class... SS>
-    void assign_slots(LuaVar &v, SS & ... stackslots) {
-        v.index_ = VARP;
-        assign_slots<RETP, ARGP, VARP+1, EXTRAP, EXTRAC>(stackslots...);
-    }
-    template<int RETP, int ARGP, int VARP, int EXTRAP, int EXTRAC, class... SS>
-    void assign_slots(LuaExtraArgs &v, SS & ... stackslots) {
-        v.index_ = EXTRAP;
-        v.size_ = EXTRAC;
-        assign_slots<RETP, ARGP, VARP, EXTRAP, EXTRAC>(stackslots...);
-    }
-    template<int RETP, int ARGP, int VARP, int EXTRAP, int EXTRAC>
-    void assign_slots() {}
-
     template<class... SS>
     void vassign_slots(int retp, int argp, int varp, int extrap, int extrac, LuaRet &v, SS & ... stackslots) {
         v.index_ = retp;
@@ -722,21 +697,24 @@ public:
     template<class... SS>
     inline LuaDefStack(lua_State *L, SS & ... stackslots) : LuaCoreStack(L) {
         constexpr Counts counts = count_slots<0, 0, 0, 0>(stackslots...);
-        if (lua_gettop(L_) < counts.narg) {
-            luaL_error(L_, "function expects at least %d arguments", counts.narg);
+        int nargs = lua_gettop(L);
+        if (counts.nextra == 0) {
+            if (nargs != counts.narg) {
+                luaL_error(L_, "function expects exactly %d arguments", counts.narg);
+            }
+        } else {
+            if (nargs < counts.narg) {
+                luaL_error(L_, "function expects at least %d arguments", counts.narg);
+            }
         }
-        lua_checkstack(L, counts.nvar + counts.nret + 20);
-        int top = lua_gettop(L);
-        for (int i = 0; i < counts.nvar + counts.nret; i ++) {
-            lua_pushnil(L_);
-        }
-        vassign_slots(1 + counts.nvar + top, 1, 1 + top, 1 + counts.narg, top - counts.narg, stackslots...);
-        top_ = top + counts.nvar + counts.nret;
+        lua_checkstack(L, counts.nret + counts.nvar + 20);
+        lua_insert_frame(L, counts.nret + counts.nvar);
+        vassign_slots(1, 1 + counts.nret + counts.nvar, 1 + counts.nret, 1 + counts.nret + counts.nvar + counts.narg, nargs - counts.narg, stackslots...);
         nret_ = counts.nret;
     }
 
     int result() {
-        lua_settop(L_, top_);
+        lua_settop(L_, nret_);
         return nret_;
     }