static void localstat (LexState *ls)
{
/* stat -> LOCAL NAME {`,' NAME} [`=' explist1] */
int nvars = 0;
int nexps;
expdesc e;
do
{
new_localvar(ls, str_checkname(ls), nvars++);
}
while (testnext(ls, ','));
if (testnext(ls, '='))
{
nexps = explist1(ls, &e);
}
else
{
e.k = VVOID;
nexps = 0;
}
adjust_assign(ls, nvars, nexps, &e);
adjustlocalvars(ls, nvars);
}
static void assignment (LexState *ls, struct LHS_assign *lh, int nvars) {
expdesc e;
check_condition(ls, VLOCAL <= lh->v.k && lh->v.k <= VINDEXED,
"syntax error");
if (testnext(ls, ',')) { /* assignment -> `,' primaryexp assignment */
struct LHS_assign nv;
nv.prev = lh;
primaryexp(ls, &nv.v);
if (nv.v.k == VLOCAL)
check_conflict(ls, lh, &nv.v);
assignment(ls, &nv, nvars+1);
}
else { /* assignment -> `=' explist1 */
int nexps;
checknext(ls, '=');
nexps = explist1(ls, &e);
if (nexps != nvars) {
adjust_assign(ls, nvars, nexps, &e);
if (nexps > nvars)
ls->fs->freereg -= nexps - nvars; /* remove extra values */
}
else {
luaK_setoneret(ls->fs, &e); /* close last expression */
luaK_storevar(ls->fs, &lh->v, &e);
return; /* avoid default */
}
}
init_exp(&e, VNONRELOC, ls->fs->freereg-1); /* default assignment */
luaK_storevar(ls->fs, &lh->v, &e);
}
static void forlist (LexState *ls, TString *indexname)
{
/* forlist -> NAME {,NAME} IN explist1 forbody */
FuncState *fs = GetCurrentFuncState( ls );
expdesc e;
int nvars = 0;
int base = fs->freereg;
/* create control variables */
new_localvarliteral(ls, "(for generator)", nvars++);
new_localvarliteral(ls, "(for state)", nvars++);
new_localvarliteral(ls, "(for control)", nvars++);
/* create declared variables */
new_localvar(ls, indexname, nvars++);
while (testnext(ls, ','))
{
new_localvar(ls, str_checkname(ls), nvars++);
}
checknext(ls, TK_IN);
int line = ls->linenumber;
adjust_assign(ls, 3, explist1(ls, &e), &e);
luaK_checkstack(fs, 3); /* extra space to call generator */
forbody(ls, base, line, nvars - 3, 0);
}
static int assignment (LexState *ls, struct LHS_assign *lh, int nvars,
lu_byte *from_var)
{
expdesc e;
int from = 0;
check_condition(ls, VLOCAL <= lh->v.k && lh->v.k <= VINDEXED,
"syntax error");
if (testnext(ls, ',')) { /* assignment -> `,' primaryexp assignment */
struct LHS_assign nv;
nv.prev = lh;
primaryexp(ls, &nv.v);
if (nv.v.k == VLOCAL)
check_conflict(ls, lh, &nv.v);
luaY_checklimit(ls->fs, nvars, LUAI_MAXCCALLS - ls->L->nCcalls,
"variables in assignment");
from = assignment(ls, &nv, nvars+1, from_var);
}
else { /* assignment -> IN primaryexp | `=' explist1 */
int nexps;
if (testnext(ls, TK_IN)) {
new_localvarliteral(ls, "(from)", 0);
primaryexp(ls, &e);
luaK_exp2nextreg(ls->fs, &e);
*from_var = ls->fs->nactvar;
adjustlocalvars(ls, 1);
luaK_setoneret(ls->fs, &e); /* close last expression */
getfrom(ls, &e, &lh->v);
luaK_storevar(ls->fs, &lh->v, &e);
return 1; /* avoid default */
}
else {
checknext(ls, '=');
nexps = explist1(ls, &e);
}
if (nexps == nvars) {
luaK_setoneret(ls->fs, &e); /* close last expression */
luaK_storevar(ls->fs, &lh->v, &e);
return 0; /* avoid default */
}
else {
adjust_assign(ls, nvars, nexps, &e);
if (nexps > nvars)
ls->fs->freereg -= nexps - nvars; /* remove extra values */
}
}
init_exp(&e, VNONRELOC, ls->fs->freereg-1); /* default assignment */
if (from) getfrom(ls, &e, &lh->v);
luaK_storevar(ls->fs, &lh->v, &e);
return from;
}
static void assignment (LexState *ls, struct LHS_assign *lh, int nvars, BinOpr *opr) {
expdesc e;
check_condition(ls, VLOCAL <= lh->v.k && lh->v.k <= VINDEXED,
"syntax error");
if (testnext(ls, ',')) { /* assignment -> `,' primaryexp assignment */
struct LHS_assign nv;
nv.prev = lh;
primaryexp(ls, &nv.v);
if (nv.v.k == VLOCAL)
check_conflict(ls, lh, &nv.v);
assignment(ls, &nv, nvars+1, opr);
}
else { /* assignment -> `=' explist1 */
int nexps;
*opr = OPR_NOBINOPR;
switch(ls->t.token)
{
case '=': break;
case TK_CONCATASSIGN: *opr = OPR_CONCAT; break;
case TK_ADDASSIGN: *opr = OPR_ADD; break;
case TK_SUBASSIGN: *opr = OPR_SUB; break;
case TK_MULASSIGN: *opr = OPR_MUL; break;
case TK_DIVASSIGN: *opr = OPR_DIV; break;
case TK_POWASSIGN: *opr = OPR_POW; break;
case TK_MODASSIGN: *opr = OPR_MOD; break;
default:
luaX_syntaxerror(ls, "unexpected symbol");
break;
};
luaX_next(ls);
nexps = explist1(ls, &e);
if (nexps != nvars) {
adjust_assign(ls, nvars, nexps, &e);
if (nexps > nvars)
ls->fs->freereg -= nexps - nvars; /* remove extra values */
}
else {
luaK_setoneret(ls->fs, &e); /* close last expression */
luaK_storevar(ls->fs, &lh->v, &e, *opr);
return; /* avoid default */
}
}
init_exp(&e, VNONRELOC, ls->fs->freereg-1); /* default assignment */
luaK_storevar(ls->fs, &lh->v, &e, *opr);
}
static void localstat (LexState *ls) {
/* stat -> LOCAL NAME {`,' NAME} [ IN primaryexp | `=' explist1] */
int nvars = 0;
int nexps;
expdesc e;
do {
new_localvar(ls, str_checkname(ls), nvars++);
} while (testnext(ls, ','));
if (testnext(ls, TK_IN)) {
lu_byte from_var;
int regs = ls->fs->freereg;
int vars = ls->fs->nactvar;
luaK_reserveregs(ls->fs, nvars);
adjustlocalvars(ls, nvars);
new_localvarliteral(ls, "(from)", 0);
primaryexp(ls, &e);
luaK_exp2nextreg(ls->fs, &e);
from_var = ls->fs->nactvar;
adjustlocalvars(ls, 1);
luaK_setoneret(ls->fs, &e); /* close last expression */
for (nexps=0; nexps<nvars; nexps++) {
expdesc v, key;
init_exp(&e, VNONRELOC, ls->fs->freereg-1);
codestring(ls, &key, getlocvar(ls->fs, vars+nexps).varname);
luaK_indexed(ls->fs, &e, &key);
init_exp(&v, VLOCAL, regs+nexps);
luaK_storevar(ls->fs, &v, &e);
}
removevars(ls, from_var);
return;
}
if (testnext(ls, '='))
nexps = explist1(ls, &e);
else {
e.k = VVOID;
nexps = 0;
}
adjust_assign(ls, nvars, nexps, &e);
adjustlocalvars(ls, nvars);
}
static void forlist (LexState *ls, TString *indexname) {
/* forlist -> NAME {,NAME} IN explist1 DO body */
FuncState *fs = ls->fs;
expdesc e;
int nvars = 0;
int line;
int base = fs->freereg;
new_localvarstr(ls, "(for generator)", nvars++);
new_localvarstr(ls, "(for state)", nvars++);
new_localvar(ls, indexname, nvars++);
while (testnext(ls, ','))
new_localvar(ls, str_checkname(ls), nvars++);
check(ls, TK_IN);
line = ls->linenumber;
adjust_assign(ls, nvars, explist1(ls, &e), &e);
luaK_checkstack(fs, 3); /* extra space to call generator */
luaK_codeAsBx(fs, OP_TFORPREP, base, NO_JUMP);
forbody(ls, base, line, nvars, 0);
}
static void assignment (LexState *ls, struct LHS_assign *lh, int nvars) {
expdesc e;
check_condition(ls, VLOCAL <= lh->v.k && lh->v.k <= VINDEXED,
"syntax error");
if (testnext(ls, ',')) { /* assignment -> `,' primaryexp assignment */
struct LHS_assign nv;
nv.prev = lh;
primaryexp(ls, &nv.v);
if (nv.v.k == VLOCAL)
check_conflict(ls, lh, &nv.v);
luaY_checklimit(ls->fs, nvars, LUAI_MAXCCALLS - ls->L->nCcalls,
"variables in assignment");
assignment(ls, &nv, nvars+1);
}
else { /* assignment -> `=' explist1 */
int nexps;
/* hook for inc_assignment */
if(nvars==1) {
switch(ls->t.token) {
case '+': case '-': case '*': case '/': case TK_CONCAT:
inc_assignment(ls,lh);
/* If you're using Shook's table unpack patch, return 0 here.*/
return;
}
}
checknext(ls, '=');
nexps = explist1(ls, &e);
if (nexps != nvars) {
adjust_assign(ls, nvars, nexps, &e);
if (nexps > nvars)
ls->fs->freereg -= nexps - nvars; /* remove extra values */
}
else {
luaK_setoneret(ls->fs, &e); /* close last expression */
luaK_storevar(ls->fs, &lh->v, &e);
return; /* avoid default */
}
}
init_exp(&e, VNONRELOC, ls->fs->freereg-1); /* default assignment */
luaK_storevar(ls->fs, &lh->v, &e);
}
static void assignment (LexState *ls, struct LHS_assign *lh, int nvars) {
expdesc e;
check_condition(ls, VLOCAL <= lh->v.k && lh->v.k <= VINDEXED,
"syntax error");
if (testnext(ls, ',')) { /* assignment -> `,' primaryexp assignment */
struct LHS_assign nv;
nv.prev = lh;
primaryexp(ls, &nv.v);
if (nv.v.k == VLOCAL)
check_conflict(ls, lh, &nv.v);
luaY_checklimit(ls->fs, nvars, LUAI_MAXCCALLS - ls->L->nCcalls,
"variables in assignment");
assignment(ls, &nv, nvars+1);
}
else { /* assignment -> `=' explist1 */
int nexps;
#if LUA_MUTATION_OPERATORS
luaX_next(ls); /* consume `=' token. */
#else
checknext(ls, '=');
#endif /* LUA_MUTATION_OPERATORS */
nexps = explist1(ls, &e);
if (nexps != nvars) {
adjust_assign(ls, nvars, nexps, &e);
if (nexps > nvars)
ls->fs->freereg -= nexps - nvars; /* remove extra values */
}
else {
luaK_setoneret(ls->fs, &e); /* close last expression */
luaK_storevar(ls->fs, &lh->v, &e);
return; /* avoid default */
}
}
init_exp(&e, VNONRELOC, ls->fs->freereg-1); /* default assignment */
luaK_storevar(ls->fs, &lh->v, &e);
}
