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) {
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 simpleexp(LexState* ls, expdesc* v)
{
/* simpleexp -> NUMBER | STRING | NIL | true | false | ... |
constructor | FUNCTION body | primaryexp */
switch (ls->t.token)
{
case TK_NUMBER:
{
init_exp(v, VKNUM, 0);
v->u.nval = ls->t.seminfo.r;
break;
}
case TK_STRING:
{
codestring(ls, v, ls->t.seminfo.ts);
break;
}
case TK_NIL:
{
init_exp(v, VNIL, 0);
break;
}
case TK_TRUE:
{
init_exp(v, VTRUE, 0);
break;
}
case TK_FALSE:
{
init_exp(v, VFALSE, 0);
break;
}
case TK_DOTS: /* vararg */
{
FuncState* fs = ls->fs;
check_condition(ls, fs->f->is_vararg,
"cannot use " LUA_QL("...") " outside a vararg function");
fs->f->is_vararg &= ~VARARG_NEEDSARG; /* don't need 'arg' */
init_exp(v, VVARARG, luaK_codeABC(fs, OP_VARARG, 0, 1, 0));
break;
}
case '{': /* constructor */
{
constructor(ls, v);
return;
}
case TK_FUNCTION:
{
luaX_next(ls);
body(ls, v, 0, ls->linenumber);
return;
}
default:
{
primaryexp(ls, v);
return;
}
}
luaX_next(ls);
}
static void exprstat (LexState *ls) {
/* stat -> func | assignment */
FuncState *fs = ls->fs;
struct LHS_assign v;
primaryexp(ls, &v.v);
if (v.v.k == VCALL) /* stat -> func */
SETARG_C(getcode(fs, &v.v), 1); /* call statement uses no results */
else { /* stat -> assignment */
v.prev = NULL;
assignment(ls, &v, 1);
}
}
static void exprstat (LexState *ls) {
/* stat -> func | assignment */
FuncState *fs = ls->fs;
struct LHS_assign v;
primaryexp(ls, &v.v);
if (v.v.k == VCALL) { /* stat -> func */
luaK_setcallreturns(fs, &v.v, 0); /* call statement uses no results */
}
else { /* stat -> assignment */
v.prev = NULL;
assignment(ls, &v, 1);
}
}
static void simpleexp (LexState *ls, expdesc *v) {
/* simpleexp -> NUMBER | STRING | NIL | constructor | FUNCTION body
| primaryexp */
switch (ls->t.token) {
case TK_NUMBER: {
init_exp(v, VK, luaK_numberK(ls->fs, ls->t.seminfo.r));
next(ls); /* must use `seminfo' before `next' */
break;
}
case TK_STRING: {
codestring(ls, v, ls->t.seminfo.ts);
next(ls); /* must use `seminfo' before `next' */
break;
}
case TK_WSTRING: {
codewstring(ls, v, ls->t.seminfo.ts);
next(ls); /* must use `seminfo' before `next' */
break;
}
case TK_NIL: {
init_exp(v, VNIL, 0);
next(ls);
break;
}
case TK_TRUE: {
init_exp(v, VTRUE, 0);
next(ls);
break;
}
case TK_FALSE: {
init_exp(v, VFALSE, 0);
next(ls);
break;
}
case '{': { /* constructor */
constructor(ls, v);
break;
}
case TK_FUNCTION: {
next(ls);
body(ls, v, 0, ls->linenumber);
break;
}
default: {
primaryexp(ls, v);
break;
}
}
}
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 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 changevalue (LexState *ls, int op) {
FuncState *fs = ls->fs;
expdesc v, e1, e2;
testnext(ls, '(');
primaryexp(ls, &v);
e1 = v;
if (v.k == VINDEXED)
luaK_reserveregs(fs, 1); /* <- this call solved the problem with indexed values */
if (testnext(ls, ',')) {
luaK_exp2nextreg(fs, &e1); /* <- this call solved the problem with indexed values, 0.32.0 */
expr(ls, &e2);
} else { /* using special opcodes is not faster */
init_exp(&e2, VKNUM, 0);
e2.u.nval = (lua_Integer)1;
}
testnext(ls, ')');
codearith(fs, op, &e1, &e2);
luaK_setoneret(fs, &e1); /* close last expression */
luaK_storevar(fs, &v, &e1);
}
static void exprstat (LexState *ls) {
#if LUA_MUTATION_OPERATORS
/* stat -> func | compound | assignment */
#else
/* stat -> func | assignment */
#endif /* LUA_MUTATION_OPERATORS */
FuncState *fs = ls->fs;
struct LHS_assign v;
primaryexp(ls, &v.v);
if (v.v.k == VCALL) /* stat -> func */
SETARG_C(getcode(fs, &v.v), 1); /* call statement uses no results */
#if LUA_MUTATION_OPERATORS
else { /* stat -> compound | assignment */
v.prev = NULL;
switch(ls->t.token) {
case TK_ADD_EQ:
case TK_SUB_EQ:
case TK_MUL_EQ:
case TK_DIV_EQ:
case TK_MOD_EQ:
case TK_POW_EQ:
compound(ls, &v);
break;
case ',':
case '=':
assignment(ls, &v, 1);
break;
default:
luaX_syntaxerror(ls,
luaO_pushfstring(ls->L,
"'+=','-=','*=', '/=', '%=', '^=', '=' expected"));
break;
}
#else
else { /* stat -> assignment */
v.prev = NULL;
assignment(ls, &v, 1);
#endif /* LUA_MUTATION_OPERATORS */
}
}
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);
}
static void primaryexp (LexState *ls, expdesc *v) {
/* primaryexp ->
prefixexp { `.' NAME | `[' exp `]' | `:' NAME funcargs | funcargs } */
FuncState *fs = ls->fs;
prefixexp(ls, v);
for (;;) {
switch (ls->t.token) {
case '.': { /* field */
field(ls, v);
break;
}
case '[': { /* `[' exp1 `]' */
expdesc key;
luaK_exp2anyreg(fs, v);
yindex(ls, &key);
luaK_indexed(fs, v, &key);
break;
}
case ':': { /* `:' NAME funcargs */
expdesc key;
luaX_next(ls);
checkname(ls, &key);
luaK_self(fs, v, &key);
funcargs(ls, v);
break;
}
#if LUA_WIDESTRING
case '(': case TK_STRING: case TK_WSTRING: case '{': { /* funcargs */
#else
case '(': case TK_STRING: case '{': { /* funcargs */
#endif /* LUA_WIDESTRING */
luaK_exp2nextreg(fs, v);
funcargs(ls, v);
break;
}
default: return;
}
}
}
static void simpleexp (LexState *ls, expdesc *v) {
#if LUA_WIDESTRING
/* simpleexp -> NUMBER | STRING | WSTRING | NIL | true | false | ... |
constructor | FUNCTION body | primaryexp */
#else
/* simpleexp -> NUMBER | STRING | NIL | true | false | ... |
constructor | FUNCTION body | primaryexp */
#endif /* LUA_WIDESTRING */
switch (ls->t.token) {
case TK_NUMBER: {
init_exp(v, VKNUM, 0);
v->u.nval = ls->t.seminfo.r;
break;
}
case TK_STRING: {
codestring(ls, v, ls->t.seminfo.ts);
break;
}
#if LUA_WIDESTRING
case TK_WSTRING: {
codewstring(ls, v, ls->t.seminfo.ts);
break;
}
#endif /* LUA_WIDESTRING */
case TK_NIL: {
init_exp(v, VNIL, 0);
break;
}
case TK_TRUE: {
init_exp(v, VTRUE, 0);
break;
}
case TK_FALSE: {
init_exp(v, VFALSE, 0);
break;
}
case TK_DOTS: { /* vararg */
FuncState *fs = ls->fs;
check_condition(ls, fs->f->is_vararg,
"cannot use " LUA_QL("...") " outside a vararg function");
fs->f->is_vararg &= ~VARARG_NEEDSARG; /* don't need 'arg' */
init_exp(v, VVARARG, luaK_codeABC(fs, OP_VARARG, 0, 1, 0));
break;
}
case '{': { /* constructor */
constructor(ls, v);
return;
}
case TK_FUNCTION: {
luaX_next(ls);
body(ls, v, 0, ls->linenumber);
return;
}
default: {
primaryexp(ls, v);
return;
}
}
luaX_next(ls);
}
static UnOpr getunopr (int op) {
switch (op) {
case TK_NOT: return OPR_NOT;
case '-': return OPR_MINUS;
case '#': return OPR_LEN;
default: return OPR_NOUNOPR;
}
}
static BinOpr getbinopr (int op) {
switch (op) {
case '+': return OPR_ADD;
case '-': return OPR_SUB;
case '*': return OPR_MUL;
case '/': return OPR_DIV;
case '%': return OPR_MOD;
#if LUA_BITFIELD_OPS
case '&': return OPR_BAND;
case '|': return OPR_BOR;
case TK_XOR: return OPR_BXOR;
case TK_SHL: return OPR_BSHL;
case TK_SHR: return OPR_BSHR;
#endif /* LUA_BITFIELD_OPS */
case '^': return OPR_POW;
case TK_CONCAT: return OPR_CONCAT;
case TK_NE: return OPR_NE;
case TK_EQ: return OPR_EQ;
case '<': return OPR_LT;
case TK_LE: return OPR_LE;
case '>': return OPR_GT;
case TK_GE: return OPR_GE;
case TK_AND: return OPR_AND;
case TK_OR: return OPR_OR;
default: return OPR_NOBINOPR;
}
}
static const struct {
lu_byte left; /* left priority for each binary operator */
lu_byte right; /* right priority */
} priority[] = { /* ORDER OPR */
#if LUA_BITFIELD_OPS
{8, 8}, {8, 8}, {8, 8}, {8, 8}, {8, 8}, /* bitwise operators */
#endif /* LUA_BITFIELD_OPS */
{6, 6}, {6, 6}, {7, 7}, {7, 7}, {7, 7}, /* `+' `-' `/' `%' */
{10, 9}, {5, 4}, /* power and concat (right associative) */
{3, 3}, {3, 3}, /* equality and inequality */
{3, 3}, {3, 3}, {3, 3}, {3, 3}, /* order */
{2, 2}, {1, 1} /* logical (and/or) */
};
#define UNARY_PRIORITY 8 /* priority for unary operators */
/*
** subexpr -> (simpleexp | unop subexpr) { binop subexpr }
** where `binop' is any binary operator with a priority higher than `limit'
*/
static BinOpr subexpr (LexState *ls, expdesc *v, unsigned int limit) {
BinOpr op;
UnOpr uop;
enterlevel(ls);
uop = getunopr(ls->t.token);
if (uop != OPR_NOUNOPR) {
luaX_next(ls);
subexpr(ls, v, UNARY_PRIORITY);
luaK_prefix(ls->fs, uop, v);
}
else simpleexp(ls, v);
/* expand while operators have priorities higher than `limit' */
op = getbinopr(ls->t.token);
while (op != OPR_NOBINOPR && priority[op].left > limit) {
expdesc v2;
BinOpr nextop;
luaX_next(ls);
luaK_infix(ls->fs, op, v);
/* read sub-expression with higher priority */
nextop = subexpr(ls, &v2, priority[op].right);
luaK_posfix(ls->fs, op, v, &v2);
op = nextop;
}
leavelevel(ls);
return op; /* return first untreated operator */
}
