concat for ropes
[
Date Prev][
Date Next][
Thread Prev][
Thread Next]
[
Date Index]
[
Thread Index]
- Subject: concat for ropes
- From: Luiz Henrique de Figueiredo <lhf@...>
- Date: Thu, 4 Dec 2008 10:09:58 -0200
Following the recent discussion about table.concat, here is some code that
supports the use of tables as ropes. It provides a single function "unrope"
which takes a rope (a table containing strings and similar subtables) and
concats it into a single string, optionally with delimiters.
Enjoy. All feedback welcome.
--lhf
/*
* lrope.c
* provides unrope
* Luiz Henrique de Figueiredo <lhf@tecgraf.puc-rio.br>
* 04 Dec 2008 10:08:49
* This code is hereby placed in the public domain.
*/
#include "lua.h"
#include "lauxlib.h"
#define MAXLEVEL 30
static int doconcat (lua_State *L, luaL_Buffer *b, int t, int needsep) {
int i;
if (t>MAXLEVEL+1) luaL_error(L, "table too deep for "LUA_QL("unrope"));
for (i=1;; i++)
{
lua_rawgeti(L,t,i);
switch (lua_type(L,-1))
{
case LUA_TNIL:
return needsep;
case LUA_TNUMBER:
case LUA_TSTRING:
if (needsep) {lua_pushvalue(L,1); luaL_addvalue(b);}
luaL_addvalue(b);
needsep=1;
break;
case LUA_TTABLE:
lua_replace(L,t+1);
needsep=doconcat(L,b,t+1,needsep);
break;
}
}
}
static int unrope (lua_State *L) {
luaL_Buffer b;
luaL_checktype(L, 1, LUA_TTABLE);
if (lua_isnoneornil(L,2)) lua_pushliteral(L,"");
lua_settop(L,2);
lua_insert(L,1);
luaL_checkstack(L,MAXLEVEL-1,"cannot grow stack");
lua_settop(L,MAXLEVEL+1);
luaL_buffinit(L,&b);
doconcat(L,&b,2,0);
luaL_pushresult(&b);
return 1;
}
LUALIB_API int luaopen_rope (lua_State *L) {
lua_register(L, "unrope", unrope);
return 0;
}
require"rope"
function test(t)
print("","["..unrope(t,"/").."]")
end
function try(t)
print(t)
assert(loadstring(t,"="..t))()
end
try"test{1,2,{3,4,{5,6},7},8,9}"
try"test{}"
try"test{1}"
try"test{1,2}"
try"test{1,2,3}"
try"test{1,2,{}}"
try"test{{}}"
try"test{{},{}}"
try"test{{1},{}}"
try"test{{},{2}}"
try"test{{1},{},3}"
try"test{{1}}"
try"test{{1},false,3}"
--do return end
try[[test{ "jan", "fev", { "mar", "abr" }, "mai", { }, "jun", { "jul" }, "ago",
{ "sep", { "oct", "nov" }},
{{{{{{{{{{{{{{{{{{{{{"dec"}}}}}}}}}}}}}}}}}}}}},
}]]
print"bye"
test{1,2,{3,4,{5,6},7},8,9}
[1/2/3/4/5/6/7/8/9]
test{}
[]
test{1}
[1]
test{1,2}
[1/2]
test{1,2,3}
[1/2/3]
test{1,2,{}}
[1/2]
test{{}}
[]
test{{},{}}
[]
test{{1},{}}
[1]
test{{},{2}}
[2]
test{{1},{},3}
[1/3]
test{{1}}
[1]
test{{1},false,3}
[1/3]
test{ "jan", "fev", { "mar", "abr" }, "mai", { }, "jun", { "jul" }, "ago",
{ "sep", { "oct", "nov" }},
{{{{{{{{{{{{{{{{{{{{{"dec"}}}}}}}}}}}}}}}}}}}}},
}
[jan/fev/mar/abr/mai/jun/jul/ago/sep/oct/nov/dec]
bye