commit 03bbe1baf190ec768690805b967571b78c8dd34b
parent f9037ae8c1ccb614e38cb56054927aef6203cfd9
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Fri, 25 Jul 2014 15:45:35 -0300
first implementation for 'table.copy'
Diffstat:
M | ltablib.c | | | 40 | +++++++++++++++++++++++++++++++++++++++- |
1 file changed, 39 insertions(+), 1 deletion(-)
diff --git a/ltablib.c b/ltablib.c
@@ -1,5 +1,5 @@
/*
-** $Id: ltablib.c,v 1.70 2014/05/16 18:53:25 roberto Exp roberto $
+** $Id: ltablib.c,v 1.71 2014/07/16 12:44:52 roberto Exp roberto $
** Library for Table Manipulation
** See Copyright Notice in lua.h
*/
@@ -132,6 +132,43 @@ static int tremove (lua_State *L) {
}
+static int tcopy (lua_State *L) {
+ TabA ta;
+ lua_Integer f = luaL_checkinteger(L, 2);
+ lua_Integer e = luaL_checkinteger(L, 3);
+ lua_Integer t;
+ int tt = 4; /* destination table */
+ /* the following restriction avoids several problems with overflows */
+ luaL_argcheck(L, f > 0, 2, "initial position must be positive");
+ if (lua_istable(L, tt))
+ t = luaL_checkinteger(L, 5);
+ else {
+ tt = 1; /* destination table is equal to source */
+ t = luaL_checkinteger(L, 4);
+ }
+ if (e >= f) { /* otherwise, nothing to move */
+ lua_Integer n, i;
+ ta.geti = (!luaL_getmetafield(L, 1, "__index")) ? lua_rawgeti : geti;
+ ta.seti = (!luaL_getmetafield(L, tt, "__newindex")) ? lua_rawseti : seti;
+ n = e - f + 1; /* number of elements to move */
+ if (t > f) {
+ for (i = n - 1; i >= 0; i--) {
+ (*ta.geti)(L, 1, f + i);
+ (*ta.seti)(L, tt, t + i);
+ }
+ }
+ else {
+ for (i = 0; i < n; i++) {
+ (*ta.geti)(L, 1, f + i);
+ (*ta.seti)(L, tt, t + i);
+ }
+ }
+ }
+ lua_pushvalue(L, tt); /* return "to table" */
+ return 1;
+}
+
+
static void addfield (lua_State *L, luaL_Buffer *b, TabA *ta, lua_Integer i) {
(*ta->geti)(L, 1, i);
if (!lua_isstring(L, -1))
@@ -318,6 +355,7 @@ static const luaL_Reg tab_funcs[] = {
{"pack", pack},
{"unpack", unpack},
{"remove", tremove},
+ {"copy", tcopy},
{"sort", sort},
{NULL, NULL}
};