From fe5c41fb8a0e1d4f130437b22667bf699851b17a Mon Sep 17 00:00:00 2001
From: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Wed, 30 Dec 1998 11:16:50 -0200
Subject: [PATCH] new functions "tinsert" and "tremove"

---
 lbuiltin.c | 35 ++++++++++++++++++++++++++++++++++-
 lvm.c      | 24 +++++++++++++-----------
 lvm.h      |  3 ++-
 3 files changed, 49 insertions(+), 13 deletions(-)

diff --git a/lbuiltin.c b/lbuiltin.c
index 7fc5a647..7b67b9fc 100644
--- a/lbuiltin.c
+++ b/lbuiltin.c
@@ -387,6 +387,37 @@ static void luaB_foreachvar (void) {
 }
 
 
+static void luaB_tinsert (void) {
+  Hash *a = gethash(1);
+  lua_Object v = lua_getparam(3);
+  int n = (int)getnarg(a);
+  int pos;
+  if (v != LUA_NOOBJECT)
+    pos = luaL_check_int(2);
+  else {  /* called with only 2 arguments */
+    v = luaL_nonnullarg(2);
+    pos = n+1;
+  }
+  luaV_setn(a, n+1);  /* increment field "n" */
+  for ( ;n>=pos; n--)
+    tablemove(a, n, n+1);
+  luaH_setint(a, pos, luaA_Address(v));
+}
+
+
+static void luaB_tremove (void) {
+  Hash *a = gethash(1);
+  int n = (int)getnarg(a);
+  int pos = luaL_opt_int(2, n);
+  TObject v = *luaH_getint(a, pos);
+  if (n <= 0) return;  /* table is "empty" */
+  luaV_setn(a, n-1);  /* decrement field "n" */
+  for ( ;pos<n; pos++)
+    tablemove(a, pos+1, pos);
+  luaA_pushobject(&v);
+}
+
+
 /*
 ** Quicksort algorithm from "Programming Pearls", pg. 112
 */
@@ -666,7 +697,9 @@ static struct luaL_reg builtin_funcs[] = {
   {"foreach", luaB_foreach},
   {"foreachi", luaB_foreachi},
   {"foreachvar", luaB_foreachvar},
-  {"sort", luaB_sort}
+  {"sort", luaB_sort},
+  {"tinsert", luaB_tinsert},
+  {"tremove", luaB_tremove}
 };
 
 
diff --git a/lvm.c b/lvm.c
index d84752a3..85e570b4 100644
--- a/lvm.c
+++ b/lvm.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lvm.c,v 1.33 1998/12/24 14:57:23 roberto Exp $
+** $Id: lvm.c,v 1.34 1998/12/27 20:25:20 roberto Exp roberto $
 ** Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -93,6 +93,16 @@ int luaV_tostring (TObject *obj) {
 }
 
 
+void luaV_setn (Hash *t, int val) {
+  TObject index, value;
+  ttype(&index) = LUA_T_STRING;
+  tsvalue(&index) = luaS_new("n");
+  ttype(&value) = LUA_T_NUMBER;
+  nvalue(&value) = val;
+  *(luaH_set(t, &index)) = value;
+}
+
+
 void luaV_closure (int nelems)
 {
   if (nelems > 0) {
@@ -275,8 +285,7 @@ void luaV_comparison (lua_Type ttype_less, lua_Type ttype_equal,
 }
 
 
-void luaV_pack (StkId firstel, int nvararg, TObject *tab)
-{
+void luaV_pack (StkId firstel, int nvararg, TObject *tab) {
   TObject *firstelem = L->stack.stack+firstel;
   int i;
   Hash *htab;
@@ -285,14 +294,7 @@ void luaV_pack (StkId firstel, int nvararg, TObject *tab)
   ttype(tab) = LUA_T_ARRAY;
   for (i=0; i<nvararg; i++)
     luaH_setint(htab, i+1, firstelem+i);
-  /* store counter in field "n" */ {
-    TObject index, extra;
-    ttype(&index) = LUA_T_STRING;
-    tsvalue(&index) = luaS_new("n");
-    ttype(&extra) = LUA_T_NUMBER;
-    nvalue(&extra) = nvararg;
-    *(luaH_set(htab, &index)) = extra;
-  }
+  luaV_setn(htab, nvararg);  /* store counter in field "n" */
 }
 
 
diff --git a/lvm.h b/lvm.h
index 38db19aa..7c9b5a8c 100644
--- a/lvm.h
+++ b/lvm.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lvm.h,v 1.4 1997/12/15 16:17:20 roberto Exp roberto $
+** $Id: lvm.h,v 1.5 1998/07/12 16:16:43 roberto Exp roberto $
 ** Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -20,6 +20,7 @@
 void luaV_pack (StkId firstel, int nvararg, TObject *tab);
 int luaV_tonumber (TObject *obj);
 int luaV_tostring (TObject *obj);
+void luaV_setn (Hash *t, int val);
 void luaV_gettable (void);
 void luaV_settable (TObject *t, int mode);
 void luaV_getglobal (TaggedString *ts);