changes in 'string.find' and 'string.gfind' (new 'string.match' and

'string.gmatch')
This commit is contained in:
Roberto Ierusalimschy 2005-07-05 11:30:38 -03:00
parent f7720bebe3
commit 8efb44b5e0
1 changed files with 43 additions and 12 deletions

View File

@ -1,5 +1,5 @@
/* /*
** $Id: lstrlib.c,v 1.116 2005/05/20 15:53:42 roberto Exp roberto $ ** $Id: lstrlib.c,v 1.117 2005/05/31 14:25:18 roberto Exp roberto $
** Standard library for string operations and pattern-matching ** Standard library for string operations and pattern-matching
** See Copyright Notice in lua.h ** See Copyright Notice in lua.h
*/ */
@ -485,15 +485,15 @@ static int push_captures (MatchState *ms, const char *s, const char *e) {
} }
static int str_find (lua_State *L) { static int str_find_aux (lua_State *L, int find) {
size_t l1, l2; size_t l1, l2;
const char *s = luaL_checklstring(L, 1, &l1); const char *s = luaL_checklstring(L, 1, &l1);
const char *p = luaL_checklstring(L, 2, &l2); const char *p = luaL_checklstring(L, 2, &l2);
ptrdiff_t init = posrelat(luaL_optinteger(L, 3, 1), l1) - 1; ptrdiff_t init = posrelat(luaL_optinteger(L, 3, 1), l1) - 1;
if (init < 0) init = 0; if (init < 0) init = 0;
else if ((size_t)(init) > l1) init = (ptrdiff_t)l1; else if ((size_t)(init) > l1) init = (ptrdiff_t)l1;
if (lua_toboolean(L, 4) || /* explicit request? */ if (find && (lua_toboolean(L, 4) || /* explicit request? */
strpbrk(p, SPECIALS) == NULL) { /* or no special characters? */ strpbrk(p, SPECIALS) == NULL)) { /* or no special characters? */
/* do a plain search */ /* do a plain search */
const char *s2 = lmemfind(s+init, l1-init, p, l2); const char *s2 = lmemfind(s+init, l1-init, p, l2);
if (s2) { if (s2) {
@ -513,18 +513,37 @@ static int str_find (lua_State *L) {
const char *res; const char *res;
ms.level = 0; ms.level = 0;
if ((res=match(&ms, s1, p)) != NULL) { if ((res=match(&ms, s1, p)) != NULL) {
lua_pushinteger(L, s1-s+1); /* start */ if (find) {
lua_pushinteger(L, res-s); /* end */ lua_pushinteger(L, s1-s+1); /* start */
return push_captures(&ms, NULL, 0) + 2; lua_pushinteger(L, res-s); /* end */
#if defined(LUA_COMPAT_FIND)
return push_captures(&ms, NULL, 0) + 2;
#else
return 2;
#endif
}
else
return push_captures(&ms, s1, res);
} }
} while (s1++<ms.src_end && !anchor); } while (s1++ < ms.src_end && !anchor);
} }
lua_pushnil(L); /* not found */ lua_pushnil(L); /* not found */
return 1; return 1;
} }
static int gfind_aux (lua_State *L) { static int str_find (lua_State *L) {
return str_find_aux(L, 1);
}
static int str_match (lua_State *L) {
return str_find_aux(L, 0);
}
static int gmatch_aux (lua_State *L) {
MatchState ms; MatchState ms;
size_t ls; size_t ls;
const char *s = lua_tolstring(L, lua_upvalueindex(1), &ls); const char *s = lua_tolstring(L, lua_upvalueindex(1), &ls);
@ -550,16 +569,22 @@ static int gfind_aux (lua_State *L) {
} }
static int gfind (lua_State *L) { static int gmatch (lua_State *L) {
luaL_checkstring(L, 1); luaL_checkstring(L, 1);
luaL_checkstring(L, 2); luaL_checkstring(L, 2);
lua_settop(L, 2); lua_settop(L, 2);
lua_pushinteger(L, 0); lua_pushinteger(L, 0);
lua_pushcclosure(L, gfind_aux, 3); lua_pushcclosure(L, gmatch_aux, 3);
return 1; return 1;
} }
static int gfind_nodef (lua_State *L) {
return luaL_error(L, LUA_QL("string.gfind") " was renamed to "
LUA_QL("string.gmatch"));
}
static void add_s (MatchState *ms, luaL_Buffer *b, static void add_s (MatchState *ms, luaL_Buffer *b,
const char *s, const char *e) { const char *s, const char *e) {
lua_State *L = ms->L; lua_State *L = ms->L;
@ -765,8 +790,10 @@ static const luaL_reg strlib[] = {
{"format", str_format}, {"format", str_format},
{"dump", str_dump}, {"dump", str_dump},
{"find", str_find}, {"find", str_find},
{"gfind", gfind}, {"gfind", gfind_nodef},
{"gmatch", gmatch},
{"gsub", str_gsub}, {"gsub", str_gsub},
{"match", str_match},
{NULL, NULL} {NULL, NULL}
}; };
@ -790,6 +817,10 @@ static void createmetatable (lua_State *L) {
*/ */
LUALIB_API int luaopen_string (lua_State *L) { LUALIB_API int luaopen_string (lua_State *L) {
luaL_openlib(L, LUA_STRLIBNAME, strlib, 0); luaL_openlib(L, LUA_STRLIBNAME, strlib, 0);
#if defined(LUA_COMPAT_GFIND)
lua_getfield(L, -1, "gmatch");
lua_setfield(L, -2, "gfind");
#endif
createmetatable(L); createmetatable(L);
return 1; return 1;
} }